Low-lying energy spectrum of the cerium dimerстатья
Статья опубликована в высокорейтинговом журнале
Информация о цитировании статьи получена из
Web of Science,
Scopus
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 18 июля 2013 г.
Аннотация:The electronic structure of Ce$_2$ is studied in a valence bond model with two $4f$ electrons localized at two cerium sites.
It is shown that the low-lying energy spectrum of the simplest cerium chemical bond is determined
by peculiarities of the occupied $4f$ states.
The model allows for an analytical solution which is discussed along with the numerical analysis.
The energy spectrum is a result of the interplay between the $4f$ valence bond exchange, the $4f$ Coulomb repulsion
and the spin-orbit coupling.
The calculated ground state is the even $\Omega=\Lambda=\Sigma=0$ level,
the lowest excitations situated at $\sim30$ K
are the odd $\Omega=\Lambda=\Sigma=0$ state and the $^{3} 6_5$ doublet $(\Omega=\pm5,\, \Lambda=\pm6,\, \Sigma=\mp1)$.
The calculated magnetic susceptibility
displays different behavior at high and low temperatures.
In the absence of the spin-orbit coupling the ground state is the ${}^3 \Sigma_g^-$ triplet.
The results are compared with other many-electron calculations and experimental data.