Academic literature on the topic 'Metal complexes Coordination compounds'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Metal complexes Coordination compounds.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Metal complexes Coordination compounds"

1

Salzer, A. "Nomenclature of Organometallic Compounds of the Transition Elements (IUPAC Recommendations 1999)." Pure and Applied Chemistry 71, no. 8 (August 30, 1999): 1557–85. http://dx.doi.org/10.1351/pac199971081557.

Full text
Abstract:
Organometallic compounds are defined as containing at least one metal-carbon bond between an organic molecule, ion, or radical and a metal. Organometallic nomenclature therefore usually combines the nomenclature of organic chemisty and that of coordination chemistry. Provisional rules outlining nomenclature for such compounds are found both in Nomenclature of Organic Chemistry, 1979 and in Nomenclature of Inorganic Chemistry, 1990This document describes the nomenclature for organometallic compounds of the transition elements, that is compounds with metal-carbon single bonds, metal-carbon multiple bonds as well as complexes with unsaturated molecules (metal-p-complexes).Organometallic compounds are considered to be produced by addition reactions and so they are named on an addition principle. The name therefore is built around the central metal atom name. Organic ligand names are derived according to the rules of organic chemistry with appropriate endings to indicate the different bonding modes. To designate the points of attachment of ligands in more complicated structures, the h, k, and m-notations are used. The final section deals with the abbreviated nomenclature for metallocenes and their derivatives.ContentsIntroduction Systems of Nomenclature2.1 Binary type nomenclature 2.2 Substitutive nomenlcature 2.3 Coordination nomenclature Coordination Nomenclature3.1 General definitions of coordination chemistry 3.2 Oxidation numbers and net charges 3.3 Formulae and names for coordination compounds Nomenclature for Organometallic Compounds of Transition Metals 4.1 Valence-electron-numbers and the 18-valence-electron-rule 4.2 Ligand names 4.2.1 Ligands coordinating by one metal-carbon single bond 4.2.2 Ligands coordinating by several metal-carbon single bonds 4.2.3 Ligands coordinating by metal-carbon multiple bonds 4.2.4 Complexes with unsaturated molecules or groups 4.3 Metallocene nomenclature
APA, Harvard, Vancouver, ISO, and other styles
2

Gupta, P. K., Dinesh Kumar, and Amit Kumar. "Preparation and Spectroscopic Characterization of Polymer-Supported Transition Metal Complexes." Asian Journal of Chemistry 31, no. 9 (July 31, 2019): 2087–90. http://dx.doi.org/10.14233/ajchem.2019.22142.

Full text
Abstract:
Novel polystyrene supported mixed Schiff base (PSCH2–LH2) and its coordination compounds with copper(II) and zirconium(IV) have been synthesized. PSCH2–LH2 has been synthesized by the reaction of chloromethylated polystyrene crosslinked with divinylbenzene (PSCH2–Cl) and the Schiff base (LH2) derived from 3-formylsalicylic acid, propylenediamine and acetylacetone. The polystyrene supported coordination compounds are of the types: [PSCH2–LCu] and [PSCH2–LZr(OH)2·DMF]. They have been synthesized by the reaction of PSCH2–LH2 and the metal salt in DMF. The coordination compounds have been characterized on the basis of elemental analyses, IR, reflectance, ESR spectral and magnetic susceptibility measurements. The shifts of the ν(C=N) (azomethine), ν(C–O) (phenolic) and ν(C–O) (enolic) stretches indicate the ONNO donor behaviour of PSCH2–LH2. The polystyrene supported Cu(II) compound is square planar and Zr(IV) compound is pentagonal bipyramidal. The coordinated solvent molecules are completely lost from metal bound coordination compound by heating them at definite temperature in an air oven for 3 h. The compound, PSCH2–LCu is paramagnetic, while PSCH2–LZr(OH)2·DMF is diamagnetic.
APA, Harvard, Vancouver, ISO, and other styles
3

Beldon, Patrick J., Sebastian Henke, Bartomeu Monserrat, Satoshi Tominaka, Norbert Stock, and Anthony K. Cheetham. "Transition metal coordination complexes of chrysazin." CrystEngComm 18, no. 27 (2016): 5121–29. http://dx.doi.org/10.1039/c5ce00792e.

Full text
Abstract:
Eleven novel coordination compounds, composed of chrysazin (1,8-dihydroxyanthraquinone) and different first-row transition metals (Fe, Co, Ni, Cu), were synthesised and the structures determined by single-crystal X-ray diffraction.
APA, Harvard, Vancouver, ISO, and other styles
4

Alsayeed, Raghda, Dalia Mahmood Jamil, Huda Ghalib Salman, and Mohammed H. Al-Mashhadani. "Synthesis of Novel Trimethoprim Complexes and Their Analysis by Ultraviolet Derivative Spectroscopy." Materials Science Forum 1021 (February 2021): 200–209. http://dx.doi.org/10.4028/www.scientific.net/msf.1021.200.

Full text
Abstract:
In this research, the actions of antibiotic trimethoprim alone and with metals combained. Then assayed through formation of base transition metal compounds as ligands have the chance to achieve an unusual arrangement and stability complexes of coordination. We show advancement in using transtional metal compounds medications for treamentt manyl human illnesses such as carcinomas, lymphomas, control of infections, anti-inflammatory disorders, diabetes, with neurological conditions. This combination with transition metal observed the interaction can be separated by derivative spectroscopic method and measure the characterization of compound by IR and UV spectroscopy.
APA, Harvard, Vancouver, ISO, and other styles
5

Kumar, Amit, Praveen Kumar Gupta, Sunil Kumar, and Dinesh Kumar. "Immobilised nickel(II), dioxomolybdenum(VI) and dioxouranium(VI) complexes on polystyrene resin." Journal of University of Shanghai for Science and Technology 23, no. 06 (June 18, 2021): 11201–1127. http://dx.doi.org/10.51201/jusst/21/05362.

Full text
Abstract:
New polystyrene supported mixed Schiff bases(PSCH 2 –LH 2 ) and their coordination compounds with nickel(II), dioxomolybdenum(VI), and dioxouranium(VI) have been synthesized. PSCH 2 –LH 2 have been synthesized by the reaction of chloromethylated polystyrene crosslinked with divinylbenzene(PSCH 2 –Cl) and the Schiff bases(LH 2 ) derived from 3-formylsalicylic acid, ethylenediamine or propylene diamine, and acetylacetone. The polystyrene-supported coordination compounds are of the types: PSCH 2 –LM(where M = Ni, MoO 2, UO 2 ). They have been synthesized by the reaction of PSCH 2 –LH 2 and the metal salt/metal coordination compounds in DMF. The coordination compounds have been characterized on the basis of elemental analyses, IR, reflectance, and magnetic susceptibility measurements. The shifts of the ν (C=N)(azomethine), ν (C–O)(phenolic) and ν (C–O)(enolic) stretches indicate the ONNO donor behavior of PSCH 2 –LH 2. The polystyrene-supported Ni(II) compound is square planar; MoO2 (VI) and UO2 (VI) compounds are octahedral and Zr(IV) compounds are pentagonal bipyramidal. The compounds, PSCH 2 –LM(where M = Ni, MoO 2, and UO 2 ) are diamagnetic.
APA, Harvard, Vancouver, ISO, and other styles
6

Assi, Hala, Georges Mouchaham, Nathalie Steunou, Thomas Devic, and Christian Serre. "Titanium coordination compounds: from discrete metal complexes to metal–organic frameworks." Chemical Society Reviews 46, no. 11 (2017): 3431–52. http://dx.doi.org/10.1039/c7cs00001d.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Cherkasova, Tatyana G., and Elizaveta V. Cherkasova. "Crystal Structures of Binuclear Coordination Rare-Earth Metal Compounds." Key Engineering Materials 670 (October 2015): 9–14. http://dx.doi.org/10.4028/www.scientific.net/kem.670.9.

Full text
Abstract:
The double complex compounds - hexa (isothiocyanate) chromates (III) of lanthanide (III) complexes with ε-caprolactam and nicotinic acid [Ln (ε-C6H11NO)8][Cr (NCS)6] and [Ln (C5H5NCOO)3(H2O)2][Cr (NCS)6]·nH2O, n=1,2 - were produced from the aqueous solutions by means of direct synthesis. The substances are studied by the spectroscopic method; their crystal structure is determined. It is found that all the complexes are of island ionic type. ε-C6H11NO complexes form triclinic system crystals - space group P ̄1, or monoclinic - space group С2/с. The nicotinic acid compositions crystallize in the monoclinic system, space group P21/n. The complexes have reversible heat-sensitive properties and can serve as the chemical sensors in the temperature-sensitive devices that are used for visual inspection of the thermal regime in various technological processes.
APA, Harvard, Vancouver, ISO, and other styles
8

Benesperi, Iacopo, Reena Singh, and Marina Freitag. "Copper Coordination Complexes for Energy-Relevant Applications." Energies 13, no. 9 (May 2, 2020): 2198. http://dx.doi.org/10.3390/en13092198.

Full text
Abstract:
Copper coordination complexes have emerged as a group of transition metal complexes that play important roles in solar energy conversion, utilization and storage, and have the potential to replace the quintessential commonly used transition metals, like Co, Pt, Ir and Ru as light sensitizers, redox mediators, electron donors and catalytic centers. The applications of copper coordination compounds in chemistry and energy related technologies are many and demonstrate their rightful place as sustainable, low toxicity and Earth-abundant alternative materials. In this perspective we show the most recent impact made by copper coordination complexes in dye-sensitized solar cells and other energy relevant applications.
APA, Harvard, Vancouver, ISO, and other styles
9

Melnik, Milan, Markku Rafael Sundberg, and Rolf Uggla. "Analysis of crystallographic and structural data of polymeric iron-alkaline metal complexes." Main Group Metal Chemistry 34, no. 5-6 (December 1, 2011): 93–126. http://dx.doi.org/10.1515/mgmc-2012-0900.

Full text
Abstract:
Abstract The present review covers almost 100 polymeric MFe (M=Li, Na, K, Rb, and Cs) compounds. The metal atoms of group 1 as partners with iron atom build up complex polymeric chains. The iron atoms are found in the oxidation states 0, +2, and +3, of which the oxidation state +3 prevails. The coordination number of the iron atom ranges from 2 to 10 (sandwiched). The coordination sphere about the main group 1 metals varies, ranging from tetrahedral to mostly trigonal bipyramid. There are also higher coordination numbers involved, namely, from 6 to 10. The most common ligand atoms are oxygen and nitrogen. There are three compounds displaying distortion isomerism. Several relationships between structural parameters are found and discussed.
APA, Harvard, Vancouver, ISO, and other styles
10

Peni, Peni, Risya Sasri, and Imelda Hotmarisi Silalahi. "Synthesis of Metal–Curcumin Complex Compounds (M = Na⁺, Mg²⁺, Cu²⁺)." Jurnal Kimia Sains dan Aplikasi 23, no. 3 (March 20, 2020): 75–82. http://dx.doi.org/10.14710/jksa.23.3.75-82.

Full text
Abstract:
Curcumin complex compound, MLn (L = curcumin; M = Na+, Mg2+, Cu2+) has been synthesized from the reaction between curcumin and metal precursors (NaCl, MgSO4.7H2O, CuCl2.2H2O) in ethanol under reflux conditions. Synthesis takes place through the reaction between the metal ions Na+, Mg2+, or Cu2+ as the central atom and curcumin as the ligand. Curcumin has been consumed after the reaction lasts for four hours, shown by thin-layer chromatography in which a new spot appears at higher Rf as the spot of curcumin disappears in the reaction mixture. Compared with the spectrum of curcumin, the FTIR spectra of the complexes show changes in the absorption bands and shifts of wave numbers particularly in absorption bands of phenolic –OH and C=O enol groups which strongly indicates the coordination of metal ions with the curcumin ligand which is proposed to be in β–1,3 diketone system. Also, the FTIR spectra of the reaction product showed typical absorption bands for the metal-oxygen group, M–O, at 524 cm–1, 670 cm–1 and 470 cm–1 in Na+–curcumin, Mg2+–curcumin and Cu2+–curcumin, respectively.
APA, Harvard, Vancouver, ISO, and other styles
More sources

Dissertations / Theses on the topic "Metal complexes Coordination compounds"

1

Sze-To, Lap, and 司徒立. "The structural chemistry of coordination compounds containing d-block or f-block metals." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B45204470.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Ghebregziabiher, Berhe Haile. "Synthesis of chiral thiourea ligands and their transition metal complexes." Thesis, Stellenbosch : Stellenbosch University, 2003. http://hdl.handle.net/10019.1/53610.

Full text
Abstract:
Thesis (MSc)--Stellenbosch University, 2003.
ENGLISH ABSTRACT: Modification of chitosan with benzoylisothiocyanate was attempted, however due to solvent problem the study was left incomplete till appropriate solvent is designed. N,N-diethyl-N -camphanoylthiourea (HL8), N-piperidyl-N '-camphanoylthiourea (HL9), N-pyrrolidyl-N -camphanoylthiourea (HL10) and N,N-diethyl-N -adamantylcarbonyl thiourea (HL11)have been synthesised and characterised for the first time. Two of these ligands HL8 and HL11, were used to form a number of transition metal complexes, namely H30+{fae-[Co(L8-S,Obn, cis-[Ni(L8-S,0)2], trans-[Cu(L8-S,0)2], translcis-[Zn(L 8_S,0)2], translcis-[Pt(L 8_S,0)2], Ag2[(HL8-S)(L-J.1-S,O)]2, translcis- [Ni(L11-S,O)2]and translcis-[Cu(L11_S,O)2]. The new products are fully characterised by means of MS, IR spectroscopy, NMR spectroscopy, elemental (C, H, Nand S) analysis and melting point determinations. The H30+{fae-[Co(L8-S,Obn, cis-[Ni(L8- S,O)2], trans-[Cu(L8-S,O)2] and Ag2[(HL8-S)(L-J.1-S,O)]2 are also characterised by Xray diffraction analysis. The structure of the new chiral N,N-dialkyl-N' -camphanoylthiourea ligand (HL8) has a significant effect on its coordination chemistry with transition metal ions. This ligand forms H30+ {fae-[Co(L8-S,Obn, cis-[Ni(L8-S,0)2], trans-[Cu(L-S,O)2] and Ag2[(HL8- S)(L8-J.1-S,O)]2 complexes with the Co(II), Ni(II), Cu(II) and Ag(I) metal ions respectively. The spectroscopic and X-ray diffraction results of these complexes indicate a bidentate mode of coordination of the ligand (with its Sand °donor atoms) to the Co(II), Ni(II) and Cu(II) metal ions. The reaction of this ligand with silver(I) however affords the formation of a binuclear silver(I) complex exhibiting monodentate and bidentate modes of coordination within the same complex. The exclusive formation of trans-[Cu(L8-S,0)2] is a new phenomenon for the HL type thiourea ligands with Sand °donor atoms. Up to this point a maximum of 15 % trans-isomer has been reported in ltterature." All the transition metal complexes made with HL8and HL11are air stable in both the liquid and solid states except the H30+{fae-[Co(L 8-S,Ob]} Interestingly the deep green fae- H30+{fae-[Co(L8-S,Obn complex is air sensitive and the Co(II) oxidizes to Co(III) in the complex by atmospheric O2. The oxidation of Co(II) to Co(III) in the complex is confirmed by 1Hand 13CNMR spectra as well as by UV-Visible spectra of the complex. The NMR spectra of the complexes indicated the presence of one isomer in each complex except for the NMR spectra of the platinum complex of the HL8 ligand. The presence of the minor trans-[Pt(L8-S,Q)21 isomer in combination with the major cis-[Pt(L8-S,Q)21 isomer in the platinum complex was indicated by the 1H, 13Cand 195ptNMR spectra of the complex.
AFRIKAANSE OPSOMMING: Pogings om chitosan met benzoylisothiocyanate te modifiseer is onvoltooid gelaat weens die gebrek aan'n geskikte oplosmiddel. N,N-diethyl-N -carnphanoylthiourea (HL8), N-piperidyl-N -camphanoylthiourea (HL9), N-pyrrolidyl-N -camphanoylthlourea (HL10) en N,N-diethyl-N -adamantylcarbonyl thiourea (HL11) is vir die eerste keer gesintetiseer en gekarakteriseer. Twee van die ligande, HL8 en HL11, is gebruik om verskeie oorgangsmetaalkomplekse te berei, nl. H30+{fac-[Co(L8-S,Ohn, cis-[Ni(L8-S,0)2], trans-[Cu(L8-S,0)2], trans/cis-[Zn(L8 - S,0)2], trans/cis-[Pt(L8-S,0)2], Ag2[(HLB-S)(L-jl-S,0)]2, trans/cis-[Ni(L11-S,0)2] en trans/cis-[Cu(L11_S,0)2]. Die nuwe produkte is volledig gekarakteriseer deur middel van MS, IR spektroskopie, KMR spektrometrie, elemente (C, H, N en S) analise en smeltpuntbepaling. Die komplekse H30+{fao-[Co(L8-S,0)3n, cis-[Ni(L8-S,0)2], trans- [Cu(L8-S,0)2] en Ag2[(HLB-S)(L-jl-S,0)]2 is ook deur middel van X-straaldiffraksieanalise gekarakteriseer. Die struktuur van die nuwe chirale N,N-dialkyl-N'-camphanoylthiourea ligand (HL8) het In beduidende invloed op die koordinasie van hierdie ligand met oorgangsmetaalione. Die ligand vorm H30+{fac-[Co(L8-S,Ohn, cis-[Ni(L8-S,0)2], trans-[Cu(L-S,0)2] en Ag2[(HL8-S)(L8-Il-S,0)]2 komplekse met Co(ll)-, Ni(II)-, Cu(II)- en Ag(I)-ione respektiewelik. Spektroskopiese en X-straaldiffraksie-analise van die komplekse toon dat die ligande op 'n bidentate wyse d.m.v. die S- en O-donoratome met Co(II), Ni(lI) en Cu(lI) koordineer. Die reaksie van hierdie ligand met Ag(I)-ione lei egter tot die vorming van 'n dikernige silwer(I)-kompleks waarin die ligande monodentaat (S) en bidentaat (S en 0) aan die metaal gebind is. Die vorming van uitsluitlik die trans-[Cu(L8-S,0)2] in die reaksie van HL8 met Cu(lI) is 'n besondere fenomeen in die chemie van hierdie tipe ligande; in die literatuur word melding gemaak van slegs een ander trans-kompleks met hierdie ligande, en dan wel met 'n maksimum opbrengs van 15%.29 Alle oorgangsmetaalkomplekse met HLB en HL11 is stabiel indien blootgestel aan lug, ongeag of die verbindings opgelos word of in die vastetoestand verkeer, behalwe H30+{fao-[Co(L8-S,Ohn. Die diep-groen gekleurde H30+{fao-[Co(L8-S,Ohn)3]} kompleks is lugsensitief; Co(lI) word deur lugsuurstof na Co(lIl) ge-oksideer. Die oksidasie in die kompleks kan deur middel van 1H en 13CKMR spektrometrie sowel as UV-sigbare spektrofotometrie bevestig word. Die KMR spektra van alle komplekse dui op die teenwoordigheid van slegs een isomeer in oplossing, behalwe in die geval van die platinum(lI) kompleks met HL8. Die teenwoordigheid van lae konsentrasies trans-[Pt(L8-S,0)2] isomeer tesame met veel hoër konsentrasies van die cis-[Pt(L8 -S,O)2] isomeer word deur 1H, 13Cen 195ptKMR spektroskopie aangedui.
APA, Harvard, Vancouver, ISO, and other styles
3

Habtu, Michael M. "A study of the transport, extraction and co-ordination chemistry of a number of thiourea ligands with a series of transition and post-transition metal ions." Thesis, Stellenbosch : Stellenbosch University, 2003. http://hdl.handle.net/10019.1/97374.

Full text
Abstract:
Thesis (MSc)--Stellenbosch University, 2003.
ENGLISH ABSTRACT: In this study, a number of mono- and di-substituted acyl(aroyl)thioureas were investigated for potential application as specific carriers (ionophores) for the transport and extraction of Ag(l) from a mixture of Co(II), Ni(II), Cu(II), Zn(II), Cd(II), and Pb(lI) ions. The experimental arrangement for the transport experiments employed a liquid membrane set up involving a 3-phase system - 2 aqueous phases (source and receiving phase) separated by a chloroform membrane incorporating the ligand. Competitive metal ion transport experiments were conducted using the liquid membrane set up. The aqueous source and receiving phases were analyzed using Atomic Absorption Spectroscopy (AAS) and results were confirmed by Inductively Coupled Plasma-Optical Emission Spectroscopy (ICPOES). The transport results show that the N,N-dialkyl-substituted-N'-acyl(aroyl) (HL) thioureas studied, with the exception of the N,N-di-(2-hydroxyethyl)-N'-benzoylthiourea (HL3 ) and N-piperidyl-N'-4-nitrobenzoylthiourea (HL9 ), were efficient and selective for Ag(I). HL9 was also selective for Ag(l) but not efficient. HL3 was selective for Cu(II). Under the experimental conditions employed, 13% Cu(lI) was transported by HL3 . Among the N,Ndialkyl- N'-aroylthioureas, maximum Ag(l) transport was obtained by using N,N-diethyl-N'-4- chlorobenzoylthiourea (HL5 ) and N,N-di-n-butyl-N'-benzoylthiourea (HL \ Under the experimental conditions employed, the percentages of Ag(l) transported by HL5 and HL 1 were 48% and 42% respectively. The transport selectivity and efficiency of 3,3,3' ,3'-tetraethyl-1 ,1'-isophthaloylbisthiourea (H2L12 ) and N,N-diethyl-N'-camphanoylthiourea (HL13)for Ag(l) were also studied. We were particularly interested, in comparing the Ag(l) transport and extraction efficiency of these ligands with that of the HL and H2L ligands. The experimental results reveal that, of all the ligands we investigated in this study, HL 13 was the most efficient and selective carrier for Ag(l) transport. The interesting result is that, depending on the ligand concentration used, HL 13 transported 71-81% of Ag(I). Competitive two-phase metal ion solvent extraction experiments were also performed under conditions similar to the transport studies. The results show that by varying the ligand concentration in the membrane phase, up to 100% Ag(l) can be selectively and efficiently extracted from the mixture of the seven metal ions. Finally, the N,N-di-(n)-butyl-N'-benzoylthiourea (HL1) ligand and its complex with Ag(l) were synthesized. Single crystals of the complex were grown for X-ray crystallography and the crystal and molecular structure of the complex was determined. The crystal structure showed that Ag(l) is bonded to the deprotonated ligand through the S,O atoms forming interesting cluster [Ag (L - S, 0)] 4 in the solid state. This structure is monoclinic and crystallizes in the space group P21!c with a = 17.805 (4) A, b = 21.759 (4) A, c = 36.438 (7) A, f3= 96.34(3)°, Z = 8 and a final R-factor of 5.4%.
AFRIKAANSE OPSOMMING: In hierdie proefskrif is 'n aantal mono- en di-gesubstitueerde asiel(ariel) tioureums ondersoek vir moontlike gebruik as ionofore (spesifieke draers) vir die transportasie en ekstraksie van Ag(l) vanuit 'n mengsel van Co(ll), Ni(II), Cu(II), Zn(II), Cd(II), Ag(l) en Pb(lI) ione. 'n Drie-fase selsisteem is gebruik vir die transportasie eksperimente, twee waterige fases (bron- en ontvang-fase) wat geskei is met die chloroform membraan fase wat die ligande bevat. Kompeterende metaalioon transportasie eksperimente is uitgevoer met behulp van hierdie vloeistof membraan stelsel. Die twee waterige fases is deur middel van Atoomabsorpsie Spektroskopie (AAS) ge-analiseer en resultate is bevestig met gebruik van Induktief-gekoppelde Plasma-Optiese Emissie Spektroskopie (IGP-OES). Die resultate het getoon dat elkeen van die N,N-dialkiel-gesubstitueerde-N'-asiel(ariel) (HL) tioureums, met uitsondering van N,N-di(2-hidroksie-etiel)-N'-benzieltioureum(HL 3) en Npiperidiel- N'-4-nitrobenzieltioureum(HL9 ), doeltreffend en selektief was vir Ag(l) transportasie. HL9 was selektief vir Ag(I), maar die transportasie waarde was nie hoog nie, dws. dit was nie doeltreffend nie. HL3 was selektief vir Cu(II). Met gebruik van ons eksperimentele kondisies is 13% Cu(lI) getransporteer deur HL 3. Van die N,N-dialkiel-N'- ariel tioureums, is maksimum transportasie van Ag(l) verkry met gebruik van N,N-dietiel- N'-4-chlorobenzieltioureum (HL5) en N,N-di-n-butiel-N'-benzieltioureum (HL1). Met gebruik van ons eksperimentele kondisies was die persentasie transportasie van Ag(l) deur HL5 en HL 1 48% en 42% onderskeidelik. Die selektiwiteit en doeltreffendheid van 3,3,3' ,3'-tetra-etiel-1 ,t-isoftaltelblstioureumtl+L 12) en N,N-di-etiel-N'-kamfonieltioureum (HL13) vir Ag(l) transportasie is ook onderneem. Ons was besonder ge-interesseerd om die Ag(l) transportasie en ekstraksie van hierdie ligande te vergelyk met dié van die HL en H2L tipe ligande. Die eksperimentele resultate het getoon dat van al die ligande wat bestudeer is, HL 13 die doeltreffendste en mees selektiewe ionofoor was. Van besondere, belang was dat, afhangend van die ligand konsentrasie wat gebruik is, HL13 71-81% Ag(l) getransporteer het. Kompeterende twee-fase metaalioon vloeistof-vloeistof ekstraksie eksperimente is ook uitgevoer onder toestande soortgelyk aan dié van die transportasie eksperimente. Die resultate toon dat met varierende ligand konsentrasie, tot soveel as 100% Ag(l) selektief en doeltreffend geëkstrakeer word vanuit 'n mengsel van die sewe metaal ione. N,N-di-n-butiel-N'-benzieltioureum (HL1 ) ligande en die kompleks daarvan met Ag(l) is ook gesintetiseer. Enkel-kristalle van die kompleks is verkry en X-straal kristallografiese analiese is onderneem. Die kristalstruktuur toon hoedat Ag(l) gebind is aan die gedeprotoneerde ligand deur die S en Q atome en toon ook interessante [Ag(L-S,Q)]4 groepe in die vaste toestand. Hierdie struktuur is monoklinies en kristaliseer in die ruimtegroep P21!c met a = 17.805(4) Á, b = 21.759(4)Á, c = 36.438(7)Á, P = 96.34(3t, z = 8 en 'n finale R-faktor van 5.4%.
APA, Harvard, Vancouver, ISO, and other styles
4

Schauer, Philip A. "Organometallic synthons for highly conjugated redox-active materials." University of Western Australia. School of Biomedical, Biomolecular and Chemical Sciences, 2009. http://theses.library.uwa.edu.au/adt-WU2009.0166.

Full text
Abstract:
[Truncated abstract] This thesis describes various synthetic approaches toward the synthesis of highly conjugated complexes incorporating multiple transition metal centres. Particular attention is given to the synthesis of mononuclear complexes that allow for the facile assembly of discrete oligo- and poly-nuclear complexes in a controlled, stepwise fashion. Conjugated multi-metallic materials are of interest on account of their unique photophysical and electronic properties, with a particular emphasis on elucidating the nature of intramolecular communication between multiple metal centres. Chapter 1 provides a survey of these topics and current research efforts in the field. Chapter 2 describes the synthesis of Group-VIII allenylidene complexes incorporating a terminal bipyridyl moiety that provides a site for further coordination. The new compound 9-hydroxy-9-ethynyl-4,5-diazafluorene was synthesised, and reaction of this proligand with a coordinatively unsaturated metal fragment yields the allenylidene complexes [MCl(PnP)2=C=C=(4,5-diazafluoren-9-yl)]PF6 (M = Ru, PnP = dppm, dppe, dmpe; M = Os, PnP = dppm) and [CpRu(dppe)=C=C=(4,5-diazafluoren- 9-yl)]PF6. The dmpe-ligated complex is particularly susceptible to decomposition, though it was possible to obtain partial spectroscopic characterisation in addition to a single-crystal X-ray structural determination. The remaining allenylidene complexes are stable compounds readily characterised by standard spectroscopic and electrochemical means, with the bis(diphosphine) complexes characterised by single crystal X-ray structural determinations. ... Reactions of the proligand with [RuCl(PnP)2]+ (PnP = dppm, dppe) led to the isolation of a product spectroscopically consistent with the formation of the target cationic allenylidene complexes, though the complexes were not readily purified and the identity of the accompanying anion was not elucidated. The new compound 4-hydroxy-4- ethynyl-cyclopentadithiophene was also prepared, though the compound was found to be highly unstable and susceptible to rapid decomposition. The derived allenylidene complexes [RuCl(PnP)2=C=C=(4-cyclopentadithiophene)]PF6 (PnP = dppm, dppe) were isolated in a pure form and the complexes stable toward spontaneous decomposition. The thienyl-derived allenylidene complexes were characterised by spectroscopic and electrochemical techniques, with a single-crystal X-ray structural determination undertaken for [RuCl(dppm)2=C=C=(4-cyclopentaditiophene)]PF6. Electrochemical properties are significantly different between the complexes, and also show significant variation between electrodes and solvents. The terminal thienyl substituents are electroactive and show one or two oxidation processes consistent with oligomerisation of the thienyl moiety in dichloromethane solvent, and in acetonitrile solvent cyclic voltammograms are consistent with the deposition of an electroactive film on the electrode surface. The electro-polymerisation of the thienylallenylidene complexes offers a promising new route toward multi-metallic allenylidene complexes.
APA, Harvard, Vancouver, ISO, and other styles
5

Wan, Chun-wai. "Spectroscopic properties and coordination chemistry of d10 metal complexes with the polypyridyl and naphthyridyl ligands /." Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B22227301.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

尹俊偉 and Chun-wai Wan. "Spectroscopic properties and coordination chemistry of d10 metal complexes with the polypyridyl and naphthyridyl ligands." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31223564.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Lesikar, Leslie Anne. "The synthesis and structural characterization of main group and transition metal complexes supported by nitrogen based ligands." [Fort Worth, Tex.] : Texas Christian University, 2008. http://etd.tcu.edu/etdfiles/available/etd-01162009-164206/unrestricted/Lesikar.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Brayshaw, Simon Keith. "Metal complexes bearing pendant alkynes and metal complexes of N-heterocyclic carbenes." University of Western Australia. School of Biomedical and Chemical Sciences, 2004. http://theses.library.uwa.edu.au/adt-WU2005.0017.

Full text
Abstract:
This thesis is comprised of two parts. The first part describes the synthesis of cyclopentadienyltungsten complexes containing a pendant alkyne group (I), and the subsequent photo-induced intramolecular coordination of the alkyne, forming complexes such as II. Compounds containing intramolecularly coordinated alkynes are rare, and this is the first example using cyclopentadiene as the core ligand. The second part describes the synthesis and structural characterisation of a number of novel metal complexes containing N-heterocyclic carbene ligands, some containing particular functionality for taylored applications. New methods were used to form complexes of rhodium, iridium, silver and gold (eg. III, IV). Structural and spectroscopic properties of the complexes were correlated with electronic characteristics of the ancillary ligands. A number of rhodium and iridium complexes (eg. IV) derived from imidazolium-linked cyclophanes were synthesised and structurally characterised. Complexes of N-heterocyclic carbenes with pendant ionic groups were synthesised, and a preliminary examination of their catalytic activity in water was performed. N-Heterocyclic carbenes complexes containing an electron withdrawing nitro group were synthesised and the effect of the nitro group on metal-ligand bonding was examined.
APA, Harvard, Vancouver, ISO, and other styles
9

Eichler, Jack Frederick. "Coordination compounds possessing stannylamines synthesis, characterization and application /." Diss., Available online, Georgia Institute of Technology, 2004:, 2004. http://etd.gatech.edu/theses/available/etd-08242004-084134/unrestricted/eichler%5Fjack%5Ff%5F200412A%5Fphd.pdf.

Full text
Abstract:
Thesis (Ph. D.)--Chemistry and Biochemistry, Georgia Institute of Technology, 2005.
William S. Rees, Jr., Committee Chair ; E. Kent Barefield, Committee Member ; Angus P. Wilkinson, Committee Member ; Z. John Zhang, Committee Member ; Dennis W. Hess, Committee Member. Includes bibliographical references.
APA, Harvard, Vancouver, ISO, and other styles
10

Le, Roux Adele. "Hard-hard and soft-soft coordination in complexes of Group 6 and Group 10 & 11 metals respectively." Thesis, Link to the online version, 2008. http://hdl.handle.net/10019/868.

Full text
APA, Harvard, Vancouver, ISO, and other styles
More sources

Books on the topic "Metal complexes Coordination compounds"

1

Basolo, Fred. Coordination chemistry. 2nd ed. [England]: Science Reviews, 1986.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
2

C, Johnson Ronald, ed. Coordination chemistry. 2nd ed. Northwood: Science Reviews, 1986.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
3

Transition metal complexes of neutral [Eta]1-carbon ligands. Heidelberg: Springer Verlag, 2010.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
4

Cornejo, Adolfo F. A. Solution and solid state studies of metal complexes of some EDTA and calixarene derivatives. Dublin: University College Dublin, 1998.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
5

Mutikainen, Ilpo. X-ray structural studies on metal complexes of uracil and orotic acid: A survey of coordination induced changes in the uracil fragment. Helsinki: Suomalainen Tiedeakatemia, 1988.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
6

Tomasik, Piotr. Pyridine-metal complexes. Edited by Ratajewicz Zbigniew, Newkome George R, and Strekowski Lucjan. New York: Wiley, 1985.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
7

Tomasik, Piotr. Pyridine-metal complexes. Edited by Ratajewicz Zbigniew, Newkome George R, and Strekowski Lucjan. New York: Wiley, 1985.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
8

Tomasik, Piotr. Pyridine-metal complexes. Edited by Ratajewicz Zbigniew, Newkome George R, and Strekowski Lucjan. New York: Wiley, 1985.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
9

Tomasik, Piotr. Pyridine-metal complexes. New York: Wiley, 1985.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
10

Zbigniew, Ratajewicz, Newkome George R, and Strękowski Lucjan, eds. Pyridine-metal complexes. New York: Wiley, 1985.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
More sources

Book chapters on the topic "Metal complexes Coordination compounds"

1

Vogler, A., and H. Kunkely. "Charge Transfer Excitation of Coordination Compounds. Generation of Reactive Intermediates." In Catalysis by Metal Complexes, 71–111. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-017-2626-9_4.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Schönherr, T. "Spectrum-Structure Correlations in Hexacoordinated Transition Metal Complexes." In Photochemistry and Photophysics of Coordination Compounds, 55–60. Berlin, Heidelberg: Springer Berlin Heidelberg, 1987. http://dx.doi.org/10.1007/978-3-642-72666-8_11.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Sakharov, Sergei G. "Dynamic Behavior of Group 5 and 6 Transition Metal Complexes with NMR." In Fluxional Organometallic and Coordination Compounds, 85–129. Chichester, UK: John Wiley & Sons, Ltd, 2005. http://dx.doi.org/10.1002/0470858451.ch3.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Price, S. J. Berners, and P. J. Sadler. "The Anticancer Activity of Metal Phosphine Complexes." In Platinum and Other Metal Coordination Compounds in Cancer Chemotherapy, 527–37. Boston, MA: Springer US, 1988. http://dx.doi.org/10.1007/978-1-4613-1717-3_61.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Yakovlev, K. I., A. I. Stetsenko, G. M. Alekseyeva, A. A. Tulub, L. B. Selderkhanova, and I. Yu Mamelkina. "Platinum (II) Complexes with Aminopyrimidines." In Platinum and Other Metal Coordination Compounds in Cancer Chemotherapy, 763–67. Boston, MA: Springer US, 1988. http://dx.doi.org/10.1007/978-1-4613-1717-3_91.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Schwarz, F., H. Schöllhorn, U. Thewalt, and B. Lippert. "1-Methylcytosin-Complexes of Pt(IV)." In Platinum and Other Metal Coordination Compounds in Cancer Chemotherapy, 728–32. Boston, MA: Springer US, 1988. http://dx.doi.org/10.1007/978-1-4613-1717-3_84.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Chan, P. K. L., K. A. Skov, B. R. James, and N. P. Farrell. "Studies on Ruthenium Nitroimidazoles Complexes as Radiosensitizers." In Platinum and Other Metal Coordination Compounds in Cancer Chemotherapy, 638–42. Boston, MA: Springer US, 1988. http://dx.doi.org/10.1007/978-1-4613-1717-3_70.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Von Angerer, E., N. Knebel, H. Schönenberger, and J. Engel. "Antitumor Activity of Zindoxifene Derived Platinum Complexes." In Platinum and Other Metal Coordination Compounds in Cancer Chemotherapy, 761–62. Boston, MA: Springer US, 1988. http://dx.doi.org/10.1007/978-1-4613-1717-3_90.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Balzani, V., M. Maestri, A. Melandri, D. Sandrini, L. Chassot, C. Cornioley-Deuschel, P. Jolliet, U. Maeder, and A. von Zelewsky. "On the Orbital Nature of the Luminescent Excited State of Orthometalated Transition Metal Complexes." In Photochemistry and Photophysics of Coordination Compounds, 71–77. Berlin, Heidelberg: Springer Berlin Heidelberg, 1987. http://dx.doi.org/10.1007/978-3-642-72666-8_13.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Kiss, F., J. Vorlíček, J. Hejl, B. Hofírek, E. Hájek, R. Blechová, M. Bohuminská, J. Novotný, and I. Závodná. "Antitumor Activity and Toxicity of Selected Platinum Complexes." In Platinum and Other Metal Coordination Compounds in Cancer Chemotherapy, 310–12. Boston, MA: Springer US, 1988. http://dx.doi.org/10.1007/978-1-4613-1717-3_34.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Metal complexes Coordination compounds"

1

Turgunov, Kambarali, and Ulli Englert. "Metal halide coordination compounds with 4(3H)-quinazolinone." In The 2nd International Online Conference on Crystals. Basel, Switzerland: MDPI, 2020. http://dx.doi.org/10.3390/iocc_2020-07334.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Lee, Taewoo, Frank Benesch, Yan Jiang, Nili Song, and Christoph G. Rose-Petruck. "Ultrafast tabletop x-ray sources and their application to XAFS measurements of transition metal coordination complexes." In Optical Science and Technology, SPIE's 48th Annual Meeting, edited by George A. Kyrala, Jean-Claude J. Gauthier, Carolyn A. MacDonald, and Ali M. Khounsary. SPIE, 2004. http://dx.doi.org/10.1117/12.508588.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Marks, Joshua, Michael Duncan, and Timothy Ward. "COORDINATION AND STRUCTURE OF LATE TRANSITION METAL CATION (Co, Rh, Pt) ACETYLENE COMPLEXES STUDIED WITH INFRARED PHOTODISSOCIATION SPECTROSCOPY." In 74th International Symposium on Molecular Spectroscopy. Urbana, Illinois: University of Illinois at Urbana-Champaign, 2019. http://dx.doi.org/10.15278/isms.2019.th09.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Gildenast, Hans, Franziska Busse, and Ulli Englert. "Competition of the Donor Atoms - Coordination Chemistry of a O,P,N tritopic Ligand - Complexes, Supramolecules and Metal-Organic Frameworks." In The 2nd International Online Conference on Crystals. Basel, Switzerland: MDPI, 2020. http://dx.doi.org/10.3390/iocc_2020-07321.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Acharya, Palash V., Denise Lin, and Vaibhav Bahadur. "Mechanisms Underlying Foam-Based Electronucleation of Hydrates." In ASME 2018 16th International Conference on Nanochannels, Microchannels, and Minichannels. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/icnmm2018-7721.

Full text
Abstract:
Nucleation of clathrate hydrates at low temperatures is constrained by very long induction (wait) times, which can range from hours to days. Electronucleation (application of an electrical potential difference across the hydrate forming solution) can significantly reduce the induction time. This work studies the use of porous open-cell foams of various materials as electronucleation electrodes. Experiments with tetrahydrofuran (THF) hydrates reveal that aluminum and carbon foam electrodes can enable voltage-dependent nucleation, with induction times dependent on the ionization tendency of the foam material. Furthermore, we observe a non-trivial dependence of the electronucleation parameters such as induction time and the recalescence temperature on the water:THF molar ratio. This study further corroborates previously developed hypotheses which associated rapid hydrate nucleation with the formation of metal-ion coordination compounds. Overall, this work studies various aspects of electronucleation with aluminum and carbon foams.
APA, Harvard, Vancouver, ISO, and other styles
6

Acharya, Palash V., Arjang Shahriari, Katherine Carpenter, and Vaibhav Bahadur. "Aluminum Foam-Based Ultrafast Electronucleation of Hydrates." In ASME 2017 Heat Transfer Summer Conference. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/ht2017-4812.

Full text
Abstract:
Nucleation of hydrates requires very long induction (wait) times, often ranging from hours to days. Electronucleation, i.e. nucleation stimulated by the presence of an electric field in the precursor solution can reduce the induction time significantly. This work reveals that porous aluminum foams enable near-instantaneous electronucleation at very low voltages. Experiments with tetrahydrofuran hydrate nucleation reveal that open-cell aluminum foam electrodes can trigger nucleation in only tens of seconds. Foam-based electrodes reduce the induction time by as much as 150X, when compared to non-foam electrodes. This work also discusses two mechanisms underlying electronucleation. These include bubble generation (due to electrolysis), and the formation of metal-ion coordination compounds. These mechanisms depend on electrode material and polarity, and affect the induction time to different extents. This work also shows that foams result in more deterministic nucleation (compared to stochastic) when compared with non-foam electrodes. Overall, electronucleation can lead to a new class of technologies for active control of formation of hydrates.
APA, Harvard, Vancouver, ISO, and other styles
7

Acharya, Palash V., Arjang Shahriari, Denise Lin, and Vaibhav Bahadur. "Mechanisms Underlying Rapid Electronucleation and Freezing of Hydrates." In ASME 2017 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/imece2017-70206.

Full text
Abstract:
Nucleation of hydrates is constrained by very long induction (wait) times, which can range from hours to days. Electronucleation (application of an electrical potential across the precursor solution) can significantly reduce the induction time for nucleation. This study shows that porous aluminum foams (open-cell) enable near-instantaneous electronucleation at very low voltages. Experiments with tetrahydrofuran hydrates reveal that aluminum foam electrodes enable voltage-dependent nucleation with induction times of only tens of seconds at voltages as low as 20 V. Foam-based electrodes can reduce the induction time by up to 150X when compared to non-foam electrodes. Furthermore, this study reveals that electronucleation can be attributed to two distinct phenomena, namely bubble generation (due to electrolysis), and the formation of metal-ion coordination compounds. These mechanisms affect the induction time to different extents and depend on electrode material and polarity. Overall, this work uncovers the benefits of using foams for formation of hydrates, with foams aiding nucleation as well as propagation of the hydrate formation front.
APA, Harvard, Vancouver, ISO, and other styles
8

Paschoal, Diego F. S., and Joyce H. C. e. Silva. "Relativistic prediction of Pt-195 NMR chemical shift using the NMR- DKH basis sets." In VIII Simpósio de Estrutura Eletrônica e Dinâmica Molecular. Universidade de Brasília, 2020. http://dx.doi.org/10.21826/viiiseedmol2020184.

Full text
Abstract:
Nuclear magnetic resonance (NMR) spectroscopy has played an important role in the discovery and design of new drugs with antitumor potential and the Pt-195 NMR has a fundamental role since the Pt-195 nucleus is very sensitive to the nature of the ligands in the coordination sphere and the oxidation state of the metal. The theoretical prediction of the Pt-195 NMR chemical shift is an extremely difficult task in which several factors must be taken into accounts, such as basis sets, electronic correlation, solvent, and relativistic effects. In an earlier study, Paschoal et al. developed the NMR-DKH basis sets and a nonrelativistic protocol for predicting the Pt-195 NMR chemical shift. The authors studied a set of 258 Pt(II) complexes and obtained a mean absolute deviation (MAD) of 168 ppm and a mean relative deviation (MRD) of 5%. However, relativistic calculations with the NMR-DKH basis sets have not been performed. Thus, the present work aims to apply the NMR-DKH in predicting the Pt-195 NMR chemical shift including the relativistic effects. The cisplatin was used as a model and its geometry was optimized and characterized as a minimum point on the potential energy surface at the B3LYP/LANL2DZ/def2-SVP/COSMO level. The Pt-195 NMR chemical shift was calculated at the DFT-Functional-DKFull/NMR-DKH/COSMO, where the functionals BP86, PBE, BLYP, PBE0, and B3LYP were tested. All calculations were carried out in NWCHEM 7.0.0 program. From the calculated results, it can be observed that the pure GGA functionals showing a better performance when compared to the hybrid functional. The best result was obtained at the BLYP-DKFull/NMR-DKH/COSMO level, where a DAM and DRM of only 34 ppm and 1.6% was found.
APA, Harvard, Vancouver, ISO, and other styles
9

Chen, Kok Hao, and Jong Hyun Choi. "DNA Oligonucleotide-Templated Nanocrystals: Synthesis and Novel Label-Free Protein Detection." In ASME 2009 International Mechanical Engineering Congress and Exposition. ASMEDC, 2009. http://dx.doi.org/10.1115/imece2009-11958.

Full text
Abstract:
Semiconductor and magnetic nanoparticles hold unique optical and magnetic properties, and great promise for bio-imaging and therapeutic applications. As part of their stable synthesis, the nanocrystal surfaces are usually capped by long chain organic moieties such as trioctylphosphine oxide. This capping serves two purposes: it saturates dangling bonds at the exposed crystalline lattice, and it prevents irreversible aggregation by stabilizing the colloid through entropic repulsion. These nanocrystals can be rendered water-soluble by either ligand exchange or overcoating, which hampers their widespread use in biological imaging and biomedical therapeutics. Here, we report a novel scheme of synthesizing fluorescent PbS and magnetic Fe3O4 nanoparticles using DNA oligonucleotides. Our method of PbS synthesis includes addition of Na2S to the mixture solution of DNA sequence and Pb acetate (at a fixed molar ratio of DNA/S2−/Pb2+ of 1:2:4) in a standard TAE buffer at room temperature in the open air. In the case of Fe3O4 particle synthesis, ferric and ferrous chloride were mixed with DNA in DI water at a molar ratio of DNA/Fe2+/Fe3+ = 1:4:8 and the particles were formed via reductive precipitation, induced by increasing pH to ∼11 with addition of ammonium hydroxide. These nanocrystals are highly stable and water-soluble immediately after the synthesis, due to DNA termination. We examined the surface chemistry between oligonucleotides and nanocrystals using FTIR spectroscopy, and found that the different chemical moieties of nucleobases passivate the particle surface. Strong coordination of primary amine and carbonyl groups provides the chemical and colloidal stabilities, leading to high particle yields (Figure 1). The resulting PbS nanocrystals have a distribution of 3–6 nm in diameter, while a broader size distribution is observed with Fe3O4 nanoparticles as shown in Figure 1b and c, respectively. A similar observation was reported with the pH change-induced Fe3O4 particles of a bimodal size distribution where superparamagnetic and ferrimagnetic magnetites co-exist. In spite of the differences, FTIR measurements suggest that the chemical nature of the oligonucleotide stabilization in this case is identical to the PbS system. As a particular application, we demonstrate that aptamer-capped PbS QD can detect a target protein based on selective charge transfer, since the oligonucleotide-templated synthesis can also serve the additional purpose of providing selective binding to a molecular target. Here, we use thrombin and a thrombin-binding aptamer as a model system. These QD have diameters of 3∼6 nm and fluoresce around 1050 nm. We find that a DNA aptamer can passivate near IR fluorescent PbS nanocrystals, rendering them water-soluble and stable against aggregation, and retain the secondary conformation needed to selectively bind to its target, thrombin, as shown in Figure 2. Importantly, we find that when the aptamer-functionalized nanoparticles binds to its target (only the target), there is a highly systematic and selective quenching of the PL, even in high concentrations of interfering proteins as shown in Figure 3a and b. Thrombin is detected within one minute with a detection limit of ∼1 nM. This PL quenching is attributed to charge transfer from functional groups on the protein to the nanocrystals. A charge transfer can suppress optical transition mechanisms as we observe a significant decrease in QD absorption with target addition (Figure 3c). Here, we rule out other possibilities including Forster resonance energy transfer (FRET) and particle aggregation, because thrombin absorb only in the UV, and we did not observe any significant change in the diffusion coefficient of the particles with the target analyte, respectively. The charge transfer-induced photobleaching of QD and carbon nanotubes was observed with amine groups, Ru-based complexes, and azobenzene compounds. This selective detection of an unlabeled protein is distinct from previously reported schemes utilizing electrochemistry, absorption, and FRET. In this scheme, the target detection by a unique, direct PL transduction is observed even in the presence of high background concentrations of interfering negatively or positively charged proteins. This mechanism is the first to selectively modulate the QD PL directly, enabling new types of label free assays and detection schemes. This direct optical transduction is possible due to oligonucleotidetemplated surface passivation and molecular recognition. This chemistry may lead to more nanoparticle-based optical and magnetic probes that can be activated in a highly chemoselective manner.
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography