The interaction-induced changes in the $^3$He shielding constant of the helium dimer have been calculated using the Full Configuration Interaction method and large basis sets. From these data the first virial coefficient for the $^3$He isotropic shielding constant in gaseous helium has been determined. At room temperature it is negligibly small, approximately -0.006 cm$^3$mol$^{-1}$ and it increases monotonically with the temperature. This behaviour is caused by the monotonic dependence of the isotropic shielding constant of He$_2$ on the interatomic distance. In addition, the non-relativistic value of the shielding constant of the isolated He atom was estimated to be $\sigma^{iso}$=59.932~ppm.
A Full Configuration Interaction calculation of the density dependence of the 3He shielding constant.
Rizzo A
2002
Abstract
The interaction-induced changes in the $^3$He shielding constant of the helium dimer have been calculated using the Full Configuration Interaction method and large basis sets. From these data the first virial coefficient for the $^3$He isotropic shielding constant in gaseous helium has been determined. At room temperature it is negligibly small, approximately -0.006 cm$^3$mol$^{-1}$ and it increases monotonically with the temperature. This behaviour is caused by the monotonic dependence of the isotropic shielding constant of He$_2$ on the interatomic distance. In addition, the non-relativistic value of the shielding constant of the isolated He atom was estimated to be $\sigma^{iso}$=59.932~ppm.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
