Abstract
Time-dependent coupled Hartree-Fock calculations of the frequency-dependent mean polarizability alpha-(omega) and its anisotropy DELTA-alpha-(omega) are presented for a wide range of molecules containing first and second row atoms. The Cauchy moments S(-2) and S(-4), which describe the dispersion in alpha-(omega), are systematically underestimated by 20% and 40%, respectively, with the 6-31G(+ sd + sp) basis set. The dispersion in DELTA-alpha-(omega) is also underestimated, typically by 50%. Many exceptions to this behavior are observed, most of which appear to be an underestimate of the experimental dispersion in DELTA-alpha-(omega) by a greater amount. This seems to be the result of systematic experimental overestimates of dispersion in DELTA-alpha-(omega) for molecules with very small Rayleigh depolarization ratios (rho-0 <10(-2)), suggesting that the vibrational Raman contribution in these experiments is not only important, but significantly frequency dependent.
| Original language | English |
|---|---|
| Pages (from-to) | 1288-1294 |
| Number of pages | 7 |
| Journal | Journal of Chemical Physics |
| Volume | 94 |
| Issue number | 2 |
| DOIs | |
| Publication status | Published - 15 Jan 1991 |
| Externally published | Yes |
Cite this
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TIME-DEPENDENT HARTREE-FOCK 2ND-ORDER MOLECULAR-PROPERTIES WITH A MODERATELY SIZED BASIS SET .1. THE FREQUENCY-DEPENDENCE OF THE DIPOLE POLARIZABILITY. / Spackman, Mark.
In: Journal of Chemical Physics, Vol. 94, No. 2, 15.01.1991, p. 1288-1294.Research output: Contribution to journal › Article
TY - JOUR
T1 - TIME-DEPENDENT HARTREE-FOCK 2ND-ORDER MOLECULAR-PROPERTIES WITH A MODERATELY SIZED BASIS SET .1. THE FREQUENCY-DEPENDENCE OF THE DIPOLE POLARIZABILITY
AU - Spackman, Mark
PY - 1991/1/15
Y1 - 1991/1/15
N2 - Time-dependent coupled Hartree-Fock calculations of the frequency-dependent mean polarizability alpha-(omega) and its anisotropy DELTA-alpha-(omega) are presented for a wide range of molecules containing first and second row atoms. The Cauchy moments S(-2) and S(-4), which describe the dispersion in alpha-(omega), are systematically underestimated by 20% and 40%, respectively, with the 6-31G(+ sd + sp) basis set. The dispersion in DELTA-alpha-(omega) is also underestimated, typically by 50%. Many exceptions to this behavior are observed, most of which appear to be an underestimate of the experimental dispersion in DELTA-alpha-(omega) by a greater amount. This seems to be the result of systematic experimental overestimates of dispersion in DELTA-alpha-(omega) for molecules with very small Rayleigh depolarization ratios (rho-0 <10(-2)), suggesting that the vibrational Raman contribution in these experiments is not only important, but significantly frequency dependent.
AB - Time-dependent coupled Hartree-Fock calculations of the frequency-dependent mean polarizability alpha-(omega) and its anisotropy DELTA-alpha-(omega) are presented for a wide range of molecules containing first and second row atoms. The Cauchy moments S(-2) and S(-4), which describe the dispersion in alpha-(omega), are systematically underestimated by 20% and 40%, respectively, with the 6-31G(+ sd + sp) basis set. The dispersion in DELTA-alpha-(omega) is also underestimated, typically by 50%. Many exceptions to this behavior are observed, most of which appear to be an underestimate of the experimental dispersion in DELTA-alpha-(omega) by a greater amount. This seems to be the result of systematic experimental overestimates of dispersion in DELTA-alpha-(omega) for molecules with very small Rayleigh depolarization ratios (rho-0 <10(-2)), suggesting that the vibrational Raman contribution in these experiments is not only important, but significantly frequency dependent.
KW - OSCILLATOR-STRENGTH DISTRIBUTIONS
KW - DISPERSION ENERGY COEFFICIENTS
KW - MULTICONFIGURATIONAL LINEAR RESPONSE
KW - POLARIZATION PROPAGATOR APPROACH
KW - FIELD METHOD CALCULATIONS
KW - DYNAMIC POLARIZABILITIES
KW - ABINITIO CALCULATION
KW - PERTURBATION-THEORY
KW - MULTIPOLE MOMENTS
KW - ORBITAL METHODS
U2 - 10.1063/1.460038
DO - 10.1063/1.460038
M3 - Article
VL - 94
SP - 1288
EP - 1294
JO - The Journal of Chemical Physics
JF - The Journal of Chemical Physics
SN - 0021-9606
IS - 2
ER -