### Resumé

Using response function methods we report calculations of the dynamic isotropic polarizability of SnH_{4} and PbH_{4} and of the relativistic corrections to it in the random phase approximation and at the correlated multiconfigurational linear response level of approximation. All relativistic corrections obtained from the use of the Darwin and mass-velocity operators to first order are included at both levels of approximation. We find that correlation and relativistic contributions are not even approximately additive for the two molecules. The importance of the relativistic corrections is smallest in the correlated calculations, as has also been observed for other properties. For SnH_{4} the correlation contribution and the pure relativistic correction are of the same order of magnitude, whereas for PbH _{4} the relativistic correction becomes more important than the correlation contribution. We report estimated Cauchy moments, obtained from fitting the dispersion of the calculated corrections as a function of ω^{2}. The frequency dependence of the nonrelativistic polarizability is most pronounced at the correlated level, mainly due to lower excitation energies in the multiconfigurational calculations than those in the random phase approximation.

Originalsprog | Engelsk |
---|---|

Tidsskrift | The Journal of Chemical Physics |

Vol/bind | 103 |

Udgave nummer | 8 |

Sider (fra-til) | 2983-2990 |

Antal sider | 8 |

ISSN | 0021-9606 |

Status | Udgivet - 1995 |

### Fingeraftryk

### Citer dette

*The Journal of Chemical Physics*,

*103*(8), 2983-2990.

}

*The Journal of Chemical Physics*, bind 103, nr. 8, s. 2983-2990.

**Relativistic corrections to molecular dynamic dipole polarizabilities.** / Kirpekar, Sheela; Oddershede, Jens; Jensen, Hans Jørgen Aagaard.

Publikation: Bidrag til tidsskrift › Tidsskriftartikel › Forskning › peer review

TY - JOUR

T1 - Relativistic corrections to molecular dynamic dipole polarizabilities

AU - Kirpekar, Sheela

AU - Oddershede, Jens

AU - Jensen, Hans Jørgen Aagaard

PY - 1995

Y1 - 1995

N2 - Using response function methods we report calculations of the dynamic isotropic polarizability of SnH4 and PbH4 and of the relativistic corrections to it in the random phase approximation and at the correlated multiconfigurational linear response level of approximation. All relativistic corrections obtained from the use of the Darwin and mass-velocity operators to first order are included at both levels of approximation. We find that correlation and relativistic contributions are not even approximately additive for the two molecules. The importance of the relativistic corrections is smallest in the correlated calculations, as has also been observed for other properties. For SnH4 the correlation contribution and the pure relativistic correction are of the same order of magnitude, whereas for PbH 4 the relativistic correction becomes more important than the correlation contribution. We report estimated Cauchy moments, obtained from fitting the dispersion of the calculated corrections as a function of ω2. The frequency dependence of the nonrelativistic polarizability is most pronounced at the correlated level, mainly due to lower excitation energies in the multiconfigurational calculations than those in the random phase approximation.

AB - Using response function methods we report calculations of the dynamic isotropic polarizability of SnH4 and PbH4 and of the relativistic corrections to it in the random phase approximation and at the correlated multiconfigurational linear response level of approximation. All relativistic corrections obtained from the use of the Darwin and mass-velocity operators to first order are included at both levels of approximation. We find that correlation and relativistic contributions are not even approximately additive for the two molecules. The importance of the relativistic corrections is smallest in the correlated calculations, as has also been observed for other properties. For SnH4 the correlation contribution and the pure relativistic correction are of the same order of magnitude, whereas for PbH 4 the relativistic correction becomes more important than the correlation contribution. We report estimated Cauchy moments, obtained from fitting the dispersion of the calculated corrections as a function of ω2. The frequency dependence of the nonrelativistic polarizability is most pronounced at the correlated level, mainly due to lower excitation energies in the multiconfigurational calculations than those in the random phase approximation.

UR - http://www.scopus.com/inward/record.url?scp=0010772685&partnerID=8YFLogxK

M3 - Journal article

AN - SCOPUS:0010772685

VL - 103

SP - 2983

EP - 2990

JO - The Journal of Chemical Physics

JF - The Journal of Chemical Physics

SN - 0021-9606

IS - 8

ER -