The retardation long-range potentials between two 1 ${\mathrm{}}^{1}$ S (or 2 ${\mathrm{}}^{3}$ S) helium atoms are calculated. The complex dynamic multipole polarizabilities of 1 ${\mathrm{}}^{1}$ S and 2 ${\mathrm{}}^{3}$ S states of helium are obtained through a variation-perturbation approach with B-spline and Slater-type basis functions in a configuration-interaction scheme. They are used to calculate the retardation long-range potentials. The retardation coefficients are examined. Their relative magnitudes are different for different systems. The possibility of an excited state of helium dimer from the 1 ${\mathrm{}}^{1}$ S--2 ${\mathrm{}}^{3}$ S ${\mathrm{He}}_{2}$ state is estimated. \textcopyright{} 1996 The American Physical Society.The retardation long-range potentials between two 1${\mathrm{}}^{1}$S (or 2${\mathrm{}}^{3}$S) helium atoms are calculated. The complex dynamic multipole polarizabilities of 1${\mathrm{}}^{1}$S and 2${\mathrm{}}^{3}$S states of helium are obtained through a variation-perturbation approach with B-spline and Slater-type basis functions in a configuration-interaction scheme. They are used to calculate the retardation long-range potentials. The retardation coefficients are examined. Their relative magnitudes are different for different systems. The possibility of an excited state of helium dimer from the 1${\mathrm{}}^{1}$S--2${\mathrm{}}^{3}$S ${\mathrm{He}}_{2}$ state is estimated. \textcopyright{} 1996 The American Physical Society.

Physical Review AMar 1, 199635 citations

Dipole polarizabilities of excited alkali-metal atoms and long-range interactions of ground- and excited-state alkali-metal atoms with helium atoms

Cheng Zhu, A. Dalgarno, S. G. Porsev +1 more

The scalar and tensor dynamic polarizabilities of the first excited $^{2}P_{1∕2,3∕2}$ states of the alkali-metal atoms $\mathrm{Na}$ , $\mathrm{K}$ , and $\mathrm{Rb}$ are calculated using relativistic many-body perturbation theory. Comparison with experimental measurements of the static polarizabilities suggests that the errors in the theoretical predictions do not exceed 1%. The dynamic polarizabilities at imaginary frequencies are employed to calculate the long-range van der Waals coefficients for the interaction of ground-state helium atoms with the excited alkali-metal atoms to a probable error of less than 2%.The scalar and tensor dynamic polarizabilities of the first excited $^{2}P_{1∕2,3∕2}$ states of the alkali-metal atoms $\mathrm{Na}$, $\mathrm{K}$, and $\mathrm{Rb}$ are calculated using relativistic many-body perturbation theory. Comparison with experimental measurements of the static polarizabilities suggests that the errors in the theoretical predictions do not exceed 1%. The dynamic polarizabilities at imaginary frequencies are employed to calculate the long-range van der Waals coefficients for the interaction of ground-state helium atoms with the excited alkali-metal atoms to a probable error of less than 2%.

Physical Review ASep 30, 200441 citations

Interactions between Excited Atoms

Henry Margenau, Neil R. Kestner

Elsevier eBooksJan 1, 19690 citations

The retardation long-range potentials between two 1

{\mathrm{}}^{1}

S (or 2

{\mathrm{}}^{3}

S) helium atoms are calculated. The complex dynamic multipole polarizabilities of 1

{\mathrm{}}^{1}

S and 2

{\mathrm{}}^{3}

S states of helium are obtained through a variation-perturbation approach with B-spline and Slater-type basis functions in a configuration-interaction scheme. They are used to calculate the retardation long-range potentials. The retardation coefficients are examined. Their relative magnitudes are different for different systems. The possibility of an excited state of helium dimer from the 1

{\mathrm{}}^{1}

S--2

{\mathrm{}}^{3}

{\mathrm{He}}_{2}

state is estimated. \textcopyright{} 1996 The American Physical Society.

The scalar and tensor dynamic polarizabilities of the first excited

^{2}P_{1∕2,3∕2}

states of the alkali-metal atoms

\mathrm{Na}

\mathrm{K}

, and

\mathrm{Rb}

are calculated using relativistic many-body perturbation theory. Comparison with experimental measurements of the static polarizabilities suggests that the errors in the theoretical predictions do not exceed 1%. The dynamic polarizabilities at imaginary frequencies are employed to calculate the long-range van der Waals coefficients for the interaction of ground-state helium atoms with the excited alkali-metal atoms to a probable error of less than 2%.