INFRARED INTENSITIES AND BOND MOMENTS IN SULPHUR DIOXIDE

1957 ◽  
Vol 35 (8) ◽  
pp. 954-960 ◽  
Author(s):  
J. E. Mayhood
Keyword(s):  
Dipole Moment ◽  
Charge Distribution ◽  
Sulphur Dioxide ◽  
Normal Coordinate ◽  
Molecular Dipole ◽  
Molecular Dipole Moment ◽  
Equilibrium Charge ◽  
Infrared Intensities ◽  
Normal Coordinate Calculation

New values have been obtained for the intensities of the three fundamentals of sulphur dioxide. They are A1 = 317 ± 8, A2 = 376±20, A3 = 2560 ± 70, in units of 1010 sec.−1 cm.−1 at S.T.P. The normal coordinate calculation gives values for the bond moment derivatives and for the molecular dipole moment which demonstrate that the amount of charge moving in all three vibrations is greater than that inferred from the equilibrium charge distribution. The involvement of unshared electrons is suggested.

scholarly journals Determining Partial Atomic Charges for Liquid Water: Assessing Electronic Structure and Charge Models

2020 ◽  
Author(s):  
Bowen Han ◽  
Christine Isborn ◽  
Liang Shi
Keyword(s):  
Electronic Structure ◽  
Dipole Moment ◽  
Charge Transfer ◽  
Liquid Water ◽  
Quantum Chemical ◽  
Water Dimer ◽  
Atomic Charges ◽  
Molecular Dipole ◽  
Molecular Dipole Moment ◽  
Partial Atomic Charges

Partial atomic charges provide an intuitive and efficient way to describe the charge distribution and the resulting intermolecular electrostatic interactions in liquid water. Many charge models exist and it is unclear which model provides the best assignment of partial atomic charges in response to the local molecular environment. In this work, we systematically scrutinize various electronic structure methods and charge models (Mulliken, Natural Population Analysis, CHelpG, RESP, Hirshfeld, Iterative Hirshfeld, and Bader) by evaluating their performance in predicting the dipole moments of isolated water, water clusters, and liquid water as well as charge transfer in the water dimer and liquid water. Although none of the seven charge models is capable of fully capturing the dipole moment increase from isolated water (1.85 D) to liquid water (about 2.9 D), the Iterative Hirshfeld method performs best for liquid water, reproducing its experimental average molecular dipole moment, yielding a reasonable amount of intermolecular charge transfer, and showing modest sensitivity to the local water environment. The performance of the charge model is dependent on the choice of the density functional and the quantum treatment of the environment. The computed molecular dipole moment of water generally increases with the percentage of the exact Hartree-Fock exchange in the functional, whereas the amount of charge transfer between molecules decreases. For liquid water, including two full solvation shells of surrounding water molecules (within about 5.5 A of the central water) in the quantum-chemical calculation converges the charges of the central water molecule. Our final pragmatic quantum-chemical charge assigning protocol for liquid water is the Iterative Hirshfeld method with M06-HF/aug-cc-pVDZ and a quantum region cutoff radius of 5.5 A.<br>

Evidence for the contribution of the lone pair to the molecular dipole moment of triarylphosphines

1975 ◽  
Vol 16 (11) ◽  
pp. 917-920 ◽  
Author(s):  
Mark P. Warchol ◽  
E.N. DiCarlo ◽  
Cynthia A. Maryanoff ◽  
Kurt Mislow
Keyword(s):  
Dipole Moment ◽  
Lone Pair ◽  
Molecular Dipole ◽  
Molecular Dipole Moment

scholarly journals Determining Partial Atomic Charges for Liquid Water: Assessing Electronic Structure and Charge Models

2020 ◽  
Author(s):  
Bowen Han ◽  
Christine Isborn ◽  
Liang Shi
Keyword(s):  
Electronic Structure ◽  
Dipole Moment ◽  
Charge Transfer ◽  
Liquid Water ◽  
Quantum Chemical ◽  
Water Dimer ◽  
Atomic Charges ◽  
Molecular Dipole ◽  
Molecular Dipole Moment ◽  
Partial Atomic Charges

Partial atomic charges provide an intuitive and efficient way to describe the charge distribution and the resulting intermolecular electrostatic interactions in liquid water. Many charge models exist and it is unclear which model provides the best assignment of partial atomic charges in response to the local molecular environment. In this work, we systematically scrutinize various electronic structure methods and charge models (Mulliken, Natural Population Analysis, CHelpG, RESP, Hirshfeld, Iterative Hirshfeld, and Bader) by evaluating their performance in predicting the dipole moments of isolated water, water clusters, and liquid water as well as charge transfer in the water dimer and liquid water. Although none of the seven charge models is capable of fully capturing the dipole moment increase from isolated water (1.85 D) to liquid water (about 2.9 D), the Iterative Hirshfeld method performs best for liquid water, reproducing its experimental average molecular dipole moment, yielding a reasonable amount of intermolecular charge transfer, and showing modest sensitivity to the local water environment. The performance of the charge model is dependent on the choice of the density functional and the quantum treatment of the environment. The computed molecular dipole moment of water generally increases with the percentage of the exact Hartree-Fock exchange in the functional, whereas the amount of charge transfer between molecules decreases. For liquid water, including two full solvation shells of surrounding water molecules (within about 5.5 A of the central water) in the quantum-chemical calculation converges the charges of the central water molecule. Our final pragmatic quantum-chemical charge assigning protocol for liquid water is the Iterative Hirshfeld method with M06-HF/aug-cc-pVDZ and a quantum region cutoff radius of 5.5 A.<br>

scholarly journals Measurement of the molecular dipole moment and the hyperfine and Λ -doublet splittings of the BΠ13 state of thallium fluoride

2020 ◽  
Vol 102 (5) ◽  
Author(s):  
N. B. Clayburn ◽  
T. H. Wright ◽  
E. B. Norrgard ◽  
D. DeMille ◽  
L. R. Hunter
Keyword(s):  
Dipole Moment ◽  
Molecular Dipole ◽  
Molecular Dipole Moment
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