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Neese F. Analytic derivative calculation of electronicg-tensors based on multireference configuration interaction wavefunctions. Mol Phys 2010. [DOI: 10.1080/00268970701549389] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Vasiliu M, Li S, Peterson KA, Feller D, Gole JL, Dixon DA. Structures and heats of formation of simple alkali metal compounds: hydrides, chlorides, fluorides, hydroxides, and oxides for Li, Na, and K. J Phys Chem A 2010; 114:4272-81. [PMID: 20201583 DOI: 10.1021/jp911735c] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Geometry parameters, frequencies, heats of formation, and bond dissociation energies are predicted for simple alkali metal compounds (hydrides, chlorides, fluorides, hydroxides and oxides) of Li, Na, and K from coupled cluster theory [CCSD(T)] calculations including core-valence correlation with the aug-cc-pwCVnZ basis set (n = D, T, Q, and 5). To accurately calculate the heats of formation, the following additional correction were included: scalar relativistic effects, atomic spin-orbit effects, and vibrational zero-point energies. For calibration purposes, the properties of some of the lithium compounds were predicted with iterative triple and quadruple excitations via CCSDT and CCSDTQ. The calculated geometry parameters, frequencies, heats of formation, and bond dissociation energies were compared with all available experimental measurements and are in excellent agreement with high-quality experimental data. High-level calculations are required to correctly predict that K(2)O is linear and that the ground state of KO is (2)Sigma(+), not (2)Pi, as in LiO and NaO. This reliable and consistent set of calculated thermodynamic data is appropriate for use in combustion and atmospheric simulations.
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Affiliation(s)
- Monica Vasiliu
- Chemistry Department, Shelby Hall, The University of Alabama, Box 870336, Tuscaloosa, Alabama 35487-0336, USA
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Goslar J, Lijewski S, Hoffmann SK, Jankowska A, Kowalak S. Structure and dynamics of S3(-) radicals in ultramarine-type pigment based on zeolite A: electron spin resonance and electron spin echo studies. J Chem Phys 2009; 130:204504. [PMID: 19485454 DOI: 10.1063/1.3124551] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
X-band electron spin resonance (ESR) spectra of S(3)(-) radicals in ultramarine analog (pigment) prepared from zeolite A and maintaining the original structure of parent zeolite were recorded in the temperature range of 4.2-380 K. Electron spin echo experiments (echo detected ESR, electron spin-lattice relaxation, and spin echo dephasing) were performed in the temperature range of 4.2-50 K. The rigid lattice g factors are g(x) = 2.0016, g(y) = 2.0505, and g(z) = 2.0355, and they are gradually averaged with temperature to the final collapse into a single line with g = 2.028 above 300 K. This is due to reorientations of S(3)(-) molecule between 12 possible orientations in the sodalite cage through the energy barrier of 2.4 kJ/mol. The low-lying orbital states of the open form of S(3)(-) molecule having C(2v) symmetry are considered and molecular orbital (MO) theory of the g factors is presented. The orbital mixing coefficients were calculated from experimental g factors and available theoretical orbital splitting. They indicate that the unpaired electron spin density in the ground state is localized mainly (about 50%) on the central sulfur atom of S(3)(-) anion radical, whereas in the excited electronic state the density is localized mainly on the lateral sulfur atoms (90%). A strong broadening of the ESR lines in directions around the twofold symmetry axis of the radical S(3)(-) molecule (z-axis) is discovered below 10 K. It is due to a distribution of the S-S-S bond angle value influencing mainly the energy of the (2)B(2)-symmetry MO. This effect is smeared out by molecular dynamics at higher temperatures. A distribution of the g factors is confirmed by the recovery of the spin system magnetization during spin-lattice relaxation measurements, which is described by a stretched exponential function. Both the spin-lattice relaxation and electron spin echo dephasing are governed by localized phonon mode of energy of about 40 cm(-1). Thus, the anion-radical S(3)(-) molecules are weakly bonded to the zeolite framework, and they do not participate in the phonon motion of the host lattice because of their own local dynamics.
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Affiliation(s)
- Janina Goslar
- Institute of Molecular Physics, Polish Academy of Sciences, Smoluchowskiego 17, 60-179 Poznan, Poland
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BRUNA PABLOJ, GREIN FRIEDRICH. Theoretical study of the vertical electronic spectra of O−2and the superoxides LiO2and NaO2. Mol Phys 2009. [DOI: 10.1080/00268979909482833] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Sterrer M, Berger T, Diwald O, Knözinger E, Allouche A. Ozonide ions on the surface of MgO nanocrystals. Top Catal 2007. [DOI: 10.1007/s11244-007-0321-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Vancoillie S, Malmqvist PA, Pierloot K. Calculation of EPR g Tensors for Transition-Metal Complexes Based on Multiconfigurational Perturbation Theory (CASPT2). Chemphyschem 2007; 8:1803-15. [PMID: 17647251 DOI: 10.1002/cphc.200700128] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The computation of the electronic g tensor by two multireference methods is presented and applied to a selection of molecules including CN, BO, AlO, GaO, InO, ZnH, ZnF, O(2), H(2)O(+), O(3) (-), and H(2)CO(+) (group A) as well as TiF(3), CuCl(4) (2-), Cu(NH(3))(4) (2+), and a series of d(1)-MOX(4) (n-) compounds, with M=V, Cr, Mo, Tc, W, Re and X=F, Cl, Br (group B). Two approaches are considered, namely, one in which spin-orbit coupling and the Zeeman effect are included using second-order perturbation theory and another one in which the Zeeman effect is added through first-order degenerate perturbation theory within the ground-state Kramers doublet. The two methods have been implemented into the MOLCAS quantum chemistry software package. The results obtained for the molecules in group A are in good agreement with experiment and with previously reported calculated g values. The results for the molecules in group B vary. While the g values for the d(1) systems are superior to previous theoretical results, those obtained for the d(9) systems are too large compared to the experimental values.
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Affiliation(s)
- Steven Vancoillie
- Department of Chemistry, University of Leuven, Celestijnenlaan 200F, 3001 Heverlee-Leuven, Belgium.
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Lee EPF, Wright TG. Structures and Vibrational Frequencies of NaO3 and NaO3+: The Ionization Energy of NaO3. J Phys Chem A 2004. [DOI: 10.1021/jp0490655] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Edmond P. F. Lee
- School of Chemistry, University of Southampton, Highfield, Southampton, UK, SO17 1BJ, Department of Applied Biology and Chemical Technology, Hong Kong Polytechnic University, Hung Hom, Hong Kong, and Department of Chemistry, University of Sussex, Falmer, Brighton, UK, BN1 9QJ
| | - Timothy G. Wright
- School of Chemistry, University of Southampton, Highfield, Southampton, UK, SO17 1BJ, Department of Applied Biology and Chemical Technology, Hong Kong Polytechnic University, Hung Hom, Hong Kong, and Department of Chemistry, University of Sussex, Falmer, Brighton, UK, BN1 9QJ
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Brownridge S, Grein F, Tatchen J, Kleinschmidt M, Marian CM. Efficient calculation of electron paramagnetic resonance g-tensors by multireference configuration interaction sum-over-state expansions, using the atomic mean-field spin–orbit method. J Chem Phys 2003. [DOI: 10.1063/1.1569243] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
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Bruna PJ, Grein F. Hyperfine coupling constants, electron-spin g-factors and vertical spectra of the X2Σ+radicals BeH, MgH, CaH and BZ+, AlZ+, GaZ+(Z = H, Li, Na, K). A theoretical study. Phys Chem Chem Phys 2003. [DOI: 10.1039/b303698g] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Bruna PJ, Grein F. Hyperfine coupling constants and electron-sping-factors of B2+, Al2+, Ga2+, BAl+, BGa+, and AlGa+: Anab initiostudy. J Chem Phys 2002. [DOI: 10.1063/1.1487828] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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Bruna PJ, Grein F. Theoretical study of the hyperfine coupling constants and electron-spin magnetic moments (g-factors) of X2Σ+ alkali-metal radicals XY± (X,Y=Li,Na,K). Chem Phys 2002. [DOI: 10.1016/s0301-0104(01)00552-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Bruna PJ, Grein F. Ab initio study of the electron-spin magnetic moments (g-factors) of C2−, CSi−, Si2−, LiC2, NaC2, and LiSi2. J Chem Phys 2000. [DOI: 10.1063/1.481723] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Bruna PJ, Grein F. Electron-Spin Magnetic Moments (g Factors) of the Oxides LiO, NaO, and the Superoxides LiO2, NaO2. An ab Initio Study. J Phys Chem A 1999. [DOI: 10.1021/jp984079u] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Pablo J. Bruna
- Department of Chemistry, University of New Brunswick, Fredericton, New Brunswick, Canada E3B 6E2
| | - Friedrich Grein
- Department of Chemistry, University of New Brunswick, Fredericton, New Brunswick, Canada E3B 6E2
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