# Ab initio correlated calculations of rare-gas dimer quadrupoles

## Abstract

This paper reports ab initio calculations of rare gas (RG=Kr, Ar, Ne, and He) dimer quadrupoles at the second order of Moeller-Plesset perturbation theory (MP2). The study reveals the crucial role of the dispersion contribution to the RG{sub 2} quadrupole in the neighborhood of the equilibrium dimer separation. The magnitude of the dispersion quadrupole is found to be much larger than that predicted by the approximate model of Hunt. As a result, the total MP2 quadrupole moment is significantly smaller than was assumed in virtually all previous related studies. An analytical model for the distance dependence of the RG{sub 2} quadrupole is proposed. The model is based on the effective-electron approach of Jansen, but replaces the original Gaussian approximation to the electron density in an RG atom by an exponential one. The role of the nonadditive contribution in RG{sub 3} quadrupoles is discussed.

- Authors:

- Algodign, LLC, Bolshaya Sadovaya 8, Moscow 123001 (Russian Federation)

- Publication Date:

- OSTI Identifier:
- 21020733

- Resource Type:
- Journal Article

- Resource Relation:
- Journal Name: Physical Review. A; Journal Volume: 76; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevA.76.042713; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 74 ATOMIC AND MOLECULAR PHYSICS; APPROXIMATIONS; ARGON; ATOMS; DIMERS; DISPERSIONS; ELECTRON CORRELATION; ELECTRON DENSITY; ELECTRONS; EQUILIBRIUM; FUNCTIONS; HELIUM; KRYPTON; MOLECULES; NEON; PERTURBATION THEORY; POTENTIAL ENERGY; QUADRUPOLE MOMENTS; QUADRUPOLES

### Citation Formats

```
Donchev, Alexander G.
```*Ab initio correlated calculations of rare-gas dimer quadrupoles*. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVA.76.042713.

```
Donchev, Alexander G.
```*Ab initio correlated calculations of rare-gas dimer quadrupoles*. United States. doi:10.1103/PHYSREVA.76.042713.

```
Donchev, Alexander G. Mon .
"Ab initio correlated calculations of rare-gas dimer quadrupoles". United States. doi:10.1103/PHYSREVA.76.042713.
```

```
@article{osti_21020733,
```

title = {Ab initio correlated calculations of rare-gas dimer quadrupoles},

author = {Donchev, Alexander G.},

abstractNote = {This paper reports ab initio calculations of rare gas (RG=Kr, Ar, Ne, and He) dimer quadrupoles at the second order of Moeller-Plesset perturbation theory (MP2). The study reveals the crucial role of the dispersion contribution to the RG{sub 2} quadrupole in the neighborhood of the equilibrium dimer separation. The magnitude of the dispersion quadrupole is found to be much larger than that predicted by the approximate model of Hunt. As a result, the total MP2 quadrupole moment is significantly smaller than was assumed in virtually all previous related studies. An analytical model for the distance dependence of the RG{sub 2} quadrupole is proposed. The model is based on the effective-electron approach of Jansen, but replaces the original Gaussian approximation to the electron density in an RG atom by an exponential one. The role of the nonadditive contribution in RG{sub 3} quadrupoles is discussed.},

doi = {10.1103/PHYSREVA.76.042713},

journal = {Physical Review. A},

number = 4,

volume = 76,

place = {United States},

year = {Mon Oct 15 00:00:00 EDT 2007},

month = {Mon Oct 15 00:00:00 EDT 2007}

}