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1

Khedkar, Abhishek, and Michael Roemelt. "Modern multireference methods and their application in transition metal chemistry." Physical Chemistry Chemical Physics 23, no. 32 (2021): 17097–112. http://dx.doi.org/10.1039/d1cp02640b.

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2

Kong, Liguo. "Orbital invariance issue in multireference methods." International Journal of Quantum Chemistry 110, no. 14 (2009): 2603–13. http://dx.doi.org/10.1002/qua.22401.

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3

Waigum, A., J. A. Black, and A. Köhn. "A generalized hybrid scheme for multireference methods." Journal of Chemical Physics 155, no. 20 (2021): 204106. http://dx.doi.org/10.1063/5.0067511.

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4

Shiozaki, Toru, and Wataru Mizukami. "Relativistic Internally Contracted Multireference Electron Correlation Methods." Journal of Chemical Theory and Computation 11, no. 10 (2015): 4733–39. http://dx.doi.org/10.1021/acs.jctc.5b00754.

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5

Harding, Lawrence B., Stephen J. Klippenstein, and James A. Miller. "Kinetics of CH + N2Revisited with Multireference Methods." Journal of Physical Chemistry A 112, no. 3 (2008): 522–32. http://dx.doi.org/10.1021/jp077526r.

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6

de Souza, Jhonathan Rosa, Matheus Morato F. de Moraes, Yuri Alexandre Aoto, and Paula Homem-de-Mello. "Can one use the electronic absorption spectra of metalloporphyrins to benchmark electronic structure methods? A case study on the cobalt porphyrin." Physical Chemistry Chemical Physics 22, no. 41 (2020): 23886–98. http://dx.doi.org/10.1039/d0cp04699j.

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7

Ruttink, Paul J. A. "On the Size Consistency of Multireference CEPA Methods." Collection of Czechoslovak Chemical Communications 70, no. 5 (2005): 638–56. http://dx.doi.org/10.1135/cccc20050638.

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Abstract (sommario):
The size consistency of various multireference coupled electron pair approaches (MRCEPA) is analysed. These methods include the MRCEPA0, MR averaged coupled pair functional (MR-ACPF), MR averaged quadratic coupled cluster (MR-AQCC), MR (singles and doubles) CEPA (MRDCEPA) and the recently proposed MR averaged CEPA (MR-ACEPA) methods. Test calculations on the O2 dimer show that a correct treatment of the variationally included (VI) terms such as in the MRDCEPA and MR-ACEPA methods is necessary for obtaining nearly size-consistent results. On the other hand, the results strongly suggest that it
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8

So/lling, Theis I., David M. Smith, Leo Radom, Mark A. Freitag, and Mark S. Gordon. "Towards multireference equivalents of the G2 and G3 methods." Journal of Chemical Physics 115, no. 19 (2001): 8758–72. http://dx.doi.org/10.1063/1.1411998.

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9

Park, Jae Woo, Rachael Al-Saadon, Matthew K. MacLeod, Toru Shiozaki, and Bess Vlaisavljevich. "Multireference Electron Correlation Methods: Journeys along Potential Energy Surfaces." Chemical Reviews 120, no. 13 (2020): 5878–909. http://dx.doi.org/10.1021/acs.chemrev.9b00496.

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10

Segarra-Martí, Javier, and Pedro B. Coto. "A theoretical study of the intramolecular charge transfer in 4-(dimethylamino)benzethyne." Phys. Chem. Chem. Phys. 16, no. 46 (2014): 25642–48. http://dx.doi.org/10.1039/c4cp03436h.

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11

Yin, Cangtao, and Kaito Takahashi. "How big is the substituent dependence of the solar photolysis rate of Criegee intermediates?" Physical Chemistry Chemical Physics 20, no. 23 (2018): 16247–55. http://dx.doi.org/10.1039/c8cp02015a.

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12

Fracchia, Francesco, Renzo Cimiraglia, and Celestino Angeli. "Assessment of Multireference Perturbation Methods for Chemical Reaction Barrier Heights." Journal of Physical Chemistry A 119, no. 21 (2015): 5490–95. http://dx.doi.org/10.1021/jp512669z.

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13

Bhaskaran-Nair, Kiran, Wenjing Ma, Sriram Krishnamoorthy, et al. "Noniterative Multireference Coupled Cluster Methods on Heterogeneous CPU–GPU Systems." Journal of Chemical Theory and Computation 9, no. 4 (2013): 1949–57. http://dx.doi.org/10.1021/ct301130u.

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14

Füsti-Molnár, László, and Péter G. Szalay. "New Versions of Approximately Extensive Corrected Multireference Configuration Interaction Methods†." Journal of Physical Chemistry 100, no. 15 (1996): 6288–97. http://dx.doi.org/10.1021/jp952840j.

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15

Shen, Jun, and ShuHua Li. "Comparison of some multireference electronic structure methods in illustrative applications." Science China Chemistry 53, no. 2 (2010): 289–96. http://dx.doi.org/10.1007/s11426-010-0034-y.

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16

Wilson, S. "Alternatives to multireference methods for the molecular electronic structure problem." International Journal of Quantum Chemistry 99, no. 6 (2004): 925–35. http://dx.doi.org/10.1002/qua.20145.

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17

Ganguly, Gaurab, Shubhrodeep Pathak, and Ankan Paul. "Unraveling the stability of cyclobutadiene complexes using aromaticity markers." Physical Chemistry Chemical Physics 23, no. 30 (2021): 16005–12. http://dx.doi.org/10.1039/d1cp01467f.

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Abstract (sommario):
Calculations employing ab initio multireference wavefunction-based methods shed light on the intriguing reversal of aromaticity during the formation of cyclobutadiene complexes from antiaromatic to aromatic regions.
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18

Ramos-Berdullas, Nicolás, Sara Gil-Guerrero, Ángeles Peña-Gallego, and Marcos Mandado. "The effect of spin polarization on the electron transport of molecular wires with diradical character." Physical Chemistry Chemical Physics 23, no. 8 (2021): 4777–83. http://dx.doi.org/10.1039/d0cp06321e.

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Spin polarized UDFT calculations reflect, contrary to RDFT, a decreasing conductance with length in molecular wires with diradical character. This method turns to be a good alternative to more expensive multireference post-SCF methods.
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19

Evangelista, Francesco A., Andrew C. Simmonett, Henry F. Schaefer III, Debashis Mukherjee, and Wesley D. Allen. "A companion perturbation theory for state-specific multireference coupled cluster methods." Physical Chemistry Chemical Physics 11, no. 23 (2009): 4728. http://dx.doi.org/10.1039/b822910d.

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20

Kurashige, Yuki. "Multireference electron correlation methods with density matrix renormalisation group reference functions." Molecular Physics 112, no. 11 (2013): 1485–94. http://dx.doi.org/10.1080/00268976.2013.843730.

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21

Szalay, Péter G., Thomas Müller, Gergely Gidofalvi, Hans Lischka, and Ron Shepard. "Multiconfiguration Self-Consistent Field and Multireference Configuration Interaction Methods and Applications." Chemical Reviews 112, no. 1 (2011): 108–81. http://dx.doi.org/10.1021/cr200137a.

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22

Taylor, Peter R., J. M. L. Martin, J. P. Francois, and R. Gijbels. "Ab initio study of the carbon (C3+) cation using multireference methods." Journal of Physical Chemistry 95, no. 17 (1991): 6530–34. http://dx.doi.org/10.1021/j100170a029.

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23

Li, Xiangzhu. "General-Model-Space State-Universal Coupled-Cluster Method: Excited States of Ozone." Collection of Czechoslovak Chemical Communications 70, no. 6 (2005): 755–70. http://dx.doi.org/10.1135/cccc20050755.

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The low-lying excited states of ozone are investigated using the recently developed general-model-space state-universal coupled-cluster methods and the results are compared with other multireference coupled-cluster and spin-adapted unitary-group coupled-cluster approaches. The role played by the choice of different molecular orbitals in coupled-cluster calculations is also explored. It is found that the low-lying 1,3B2 states are particularly sensitive to the choice of the molecular orbitals. This observation explains some significant differences between the results obtained with spin-adapted
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24

Mášik, Jozef, Pavel Mach, Ján Urban, Martin Polášek, Peter Babinec, and Ivan Hubač. "Single-Root Multireference Brillouin-Wigner Coupled-Cluster Theory. Rotational Barrier of the Ethylene Molecule." Collection of Czechoslovak Chemical Communications 63, no. 8 (1998): 1213–22. http://dx.doi.org/10.1135/cccc19981213.

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Recently developed single-root multireference Brillouin-Wigner coupled cluster (MR BWCC) theory is applied to study the rotational barrier of the ethylene molecule. The method belongs to a broad family of state-selective coupled-cluster (CC) methods and may be considered as a bridge connecting the single-reference and multireference CC theories. In a highly nondegenerate case, it becomes identical with the standard single-reference CC method while in a quasi-degenerate case gives results very close to the Hilbert space MR CC method. The method switches between the two cases in a continuous way
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25

Jardali, F., M. Korek, and G. Younes. "Theoretical calculation of the low-lying doublet electronic states of the SrF molecule." Canadian Journal of Physics 92, no. 10 (2014): 1223–31. http://dx.doi.org/10.1139/cjp-2013-0670.

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The potential energy curves of the low-lying doublet electronic states in the representation 2s+1Λ(+/−) of the SrF molecule have been investigated by using the complete active space self-consistent field with multireference configuration interaction and multireference Rayleigh–Schrödinger perturbation theory methods. The harmonic frequency, ωe; the internuclear distance, Re; the dipole moment; and the electronic energy with respect to the ground state, Te, have been calculated for the considered electronic states. The eigenvalues, Ev; the rotational constants, Bv; and the abscissas of the turn
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26

Vos, Eva, Inés Corral, M. Merced Montero-Campillo, et al. "Spontaneous bond dissociation cascades induced by Ben clusters (n = 2,4)." Physical Chemistry Chemical Physics 23, no. 11 (2021): 6448–54. http://dx.doi.org/10.1039/d0cp06009g.

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Be<sub>4</sub> clusters are very powerful Lewis acids leading to the total dissociation of all the bonds of the Lewis bases interacting with them. The product of the bond dissociation cascade possesses a hyper-coordinated center. Multireference methods are needed to correctly describe these complexes.
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27

Ivanov, Vladimir V., Dmitry I. Lyakh, and Ludwik Adamowicz. "Multireference state-specific coupled-cluster methods. State-of-the-art and perspectives." Physical Chemistry Chemical Physics 11, no. 14 (2009): 2355. http://dx.doi.org/10.1039/b818590p.

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28

Shepard, Ron, Gary S. Kedziora, Hans Lischka, et al. "The accuracy of molecular bond lengths computed by multireference electronic structure methods." Chemical Physics 349, no. 1-3 (2008): 37–57. http://dx.doi.org/10.1016/j.chemphys.2008.03.009.

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29

Kucharski, S. A., A. Balková, P. G. Szalay, and Rodney J. Bartlett. "Hilbert space multireference coupled‐cluster methods. II. A model study on H8." Journal of Chemical Physics 97, no. 6 (1992): 4289–300. http://dx.doi.org/10.1063/1.463931.

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30

Perrine, Trilisa M., Rajat K. Chaudhuri, and Karl F. Freed. "Quadratic Padé approximants and the intruder state problem of multireference perturbation methods." International Journal of Quantum Chemistry 105, no. 1 (2005): 18–33. http://dx.doi.org/10.1002/qua.20648.

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31

LI, XIANGZHU, and JOSEF PALDUS. "REDUCED MULTIREFERENCE COUPLED-CLUSTER METHOD AND ITS APPLICATION TO THE PYRIDYNE DIRADICALS." Journal of Theoretical and Computational Chemistry 07, no. 04 (2008): 805–20. http://dx.doi.org/10.1142/s0219633608004131.

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Abstract (sommario):
The reduced multireference (RMR) coupled-cluster (CC) method with singles and doubles (RMR CCSD) that employs a modest-size MR CISD wave function as an external source for the most important (primary) triples and quadruples in order to account for the nondynamic correlation effects in the presence of quasidegeneracy, and which is further perturbatively corrected for the remaining (secondary) triples, RMR CCSD(T), is employed to compute the molecular geometry and the energy of the lowest-lying singlet and triplet states, as well as the corresponding singlet–triplet splitting, for all possible i
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32

Brabec, Jiří, Kiran Bhaskaran-Nair, Niranjan Govind, Jiří Pittner, and Karol Kowalski. "Communication: Application of state-specific multireference coupled cluster methods to core-level excitations." Journal of Chemical Physics 137, no. 17 (2012): 171101. http://dx.doi.org/10.1063/1.4764355.

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33

Oakley, Meagan S., Jie J. Bao, Mariusz Klobukowski, Donald G. Truhlar, and Laura Gagliardi. "Multireference Methods for Calculating the Dissociation Enthalpy of Tetrahedral P4 to Two P2." Journal of Physical Chemistry A 122, no. 26 (2018): 5742–49. http://dx.doi.org/10.1021/acs.jpca.7b12366.

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34

Kucharski, Stanislaw A., and Rodney J. Bartlett. "Hilbert space multireference coupled‐cluster methods. I. The single and double excitation model." Journal of Chemical Physics 95, no. 11 (1991): 8227–38. http://dx.doi.org/10.1063/1.461301.

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35

Bhaskaran-Nair, Kiran, and Karol Kowalski. "Note: Excited state studies of ozone using state-specific multireference coupled cluster methods." Journal of Chemical Physics 137, no. 21 (2012): 216101. http://dx.doi.org/10.1063/1.4769775.

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36

Roskop, Luke B., Edward F. Valeev, Emily A. Carter, Mark S. Gordon, and Theresa L. Windus. "Spin-Free [2]R12 Basis Set Incompleteness Correction to the Local Multireference Configuration Interaction and the Local Multireference Average Coupled Pair Functional Methods." Journal of Chemical Theory and Computation 12, no. 7 (2016): 3176–84. http://dx.doi.org/10.1021/acs.jctc.6b00315.

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37

Li, Chenyang, and Francesco A. Evangelista. "Multireference Theories of Electron Correlation Based on the Driven Similarity Renormalization Group." Annual Review of Physical Chemistry 70, no. 1 (2019): 245–73. http://dx.doi.org/10.1146/annurev-physchem-042018-052416.

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Abstract (sommario):
The driven similarity renormalization group (DSRG) provides an alternative way to address the intruder state problem in quantum chemistry. In this review, we discuss recent developments of multireference methods based on the DSRG. We provide a pedagogical introduction to the DSRG and its various extensions and discuss its formal properties in great detail. In addition, we report several illustrative applications of the DSRG to molecular systems.
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38

Bittererová, Martina, Stanislav Biskupič, Hans Lischka та Viliam Klimo. "Ab initio Study of the Potential Curves for CO (X1Σ+), CH (X2Π) and OH (X2Π)". Collection of Czechoslovak Chemical Communications 59, № 6 (1994): 1241–50. http://dx.doi.org/10.1135/cccc19941241.

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Calculations on spectroscopic properties of the diatomic systems CO, CH, and OH have been carried out by the multiconfiguration SCF, single reference and multireference single and double excitation CI, and average coupled pair functional methods. An evaluation of the different theoretical approaches is performed in order to get better insight into the selection of appropriate procedures for the calculation of the potential energy surface of the H + CO system.
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39

Mennucci, Benedetta, Alessandro Toniolo, and Chiara Cappelli. "Multireference perturbation configuration interaction methods for solvated systems described within the polarizable continuum model." Journal of Chemical Physics 111, no. 16 (1999): 7197–208. http://dx.doi.org/10.1063/1.480048.

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40

Chattopadhyay, Sudip, Rajat K. Chaudhuri, and Uttam Sinha Mahapatra. "Application of improved virtual orbital based multireference methods to N2, LiF, and C4H6 systems." Journal of Chemical Physics 129, no. 24 (2008): 244108. http://dx.doi.org/10.1063/1.3046454.

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41

Aprà, E., and K. Kowalski. "Implementation of High-Order Multireference Coupled-Cluster Methods on Intel Many Integrated Core Architecture." Journal of Chemical Theory and Computation 12, no. 3 (2016): 1129–38. http://dx.doi.org/10.1021/acs.jctc.5b00957.

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42

Seleznev, Alexey O., and Vladimir F. Khrustov. "Spin-tensor multireference first-order polarization propagator approximation in comparison with several multireference methods on the example of low-lying electronic states of the CH+ ion." Computational and Theoretical Chemistry 1175 (April 2020): 112733. http://dx.doi.org/10.1016/j.comptc.2020.112733.

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43

Li, Xiangzhu, and Josef Paldus. "Partially linearized, fully size-extensive, and reduced multireference coupled-cluster methods. II. Applications and performance." Journal of Chemical Physics 128, no. 14 (2008): 144119. http://dx.doi.org/10.1063/1.2868768.

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44

Ben Amor, Nadia, Sophie Hoyau, Daniel Maynau, and Valérie Brenner. "Low-lying excited states of model proteins: Performances of the CC2 method versus multireference methods." Journal of Chemical Physics 148, no. 18 (2018): 184105. http://dx.doi.org/10.1063/1.5025942.

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45

Li, Chenyang, Roland Lindh, and Francesco A. Evangelista. "Dynamically weighted multireference perturbation theory: Combining the advantages of multi-state and state-averaged methods." Journal of Chemical Physics 150, no. 14 (2019): 144107. http://dx.doi.org/10.1063/1.5088120.

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46

Kaldor, Uzi. "Multireference many-body methods. Perspective on "Linked-cluster expansions for the nuclear many-body problem"." Theoretical Chemistry Accounts: Theory, Computation, and Modeling (Theoretica Chimica Acta) 103, no. 3-4 (2000): 276–77. http://dx.doi.org/10.1007/s002149900014.

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47

Jeong, WooSeok, Samuel J. Stoneburner, Daniel King, et al. "Automation of Active Space Selection for Multireference Methods via Machine Learning on Chemical Bond Dissociation." Journal of Chemical Theory and Computation 16, no. 4 (2020): 2389–99. http://dx.doi.org/10.1021/acs.jctc.9b01297.

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48

Chattopadhyay, Sudip, Dola Pahari, Debashis Mukherjee, and Uttam Sinha Mahapatra. "A state-specific approach to multireference coupled electron-pair approximation like methods: Development and applications." Journal of Chemical Physics 120, no. 13 (2004): 5968–86. http://dx.doi.org/10.1063/1.1650328.

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49

Hamade, Y., F. Taher, M. Choueib, and Y. Monteil. "Theoretical electronic investigation of the low-lying electronic states of the LuF molecule." Canadian Journal of Physics 87, no. 11 (2009): 1163–69. http://dx.doi.org/10.1139/p09-077.

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Abstract (sommario):
The theoretical electronic structure of the LuF molecule is investigated, using the Complete Active-Space Self-Consistent Field CASSCF and the MultiReference Configuration Interaction MRCI methods. These methods are performed for 26 electronic states in the representation 2s+1Λ(+/−), neglecting spin–orbit effects. Spectroscopic constants including the harmonic vibrational wave number ωe (cm–1), the relative electronic energy Te (cm–1) referred to the ground state and the equilibrium internuclear distance Re (Å) are predicted for all the singlet and triplet electronic states situated below 50 0
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50

Stojanovic, Ljiljana. "Ab initio study of vibronic transitions between x2π and 12Σ+ electronic states of HCP+ ion". Journal of the Serbian Chemical Society 78, № 7 (2013): 973–86. http://dx.doi.org/10.2298/jsc121115128s.

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Abstract (sommario):
The ground and low-lying excited doublet electronic states of the HCP+ ion were studied by means of multireference configuration interaction method. Vibronic energy levels of the X2? state of ?, ?, ?, and ? symmetry, up to the 2500 cm-1, have been calculated variationally, employing previously developed ab initio methods which take into account vibronic and spin-orbit interactions. Obtained vibronic wave functions were used to estimate transition moments between vibronic energy levels of the X2? and 12?+ electronic states. Results were compared to available experimental and theoretical data.
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