Correlated Wavefunctions for the Ground State of Hminus;, He, and Liplus;

摘要

Energies are calculated variationally using a closedhyphen;shell orbital product times the correlation functiongathinsp;equals;thinsp;lsqb;1thinsp;plus;thinsp;lgr;r12thinsp;plus;thinsp;mgr;lpar;r1thinsp;minus;thinsp;r2rpar;2thinsp;plus;thinsp;ngr;r122lpar;r1thinsp;plus;thinsp;r2rpar;minus;nrsqb;1sol;2lpar;nthinsp;equals;thinsp;1or2rpar;. Energy errors for Hminus;, He, and Liplus;, respectively, are 0.00193, 0.00019, and 0.00021 a.u. whennthinsp;equals;thinsp;1and 0.00229, 0.00025, and 0.00064 a.u. whennthinsp;equals;thinsp;2orngr;thinsp;equals;thinsp;0. An explanation is proposed for the fact thatgais much more accurate for He and Liplus;than for Hminus;, whereas the opposite is true for the correlation functiongbthinsp;equals;thinsp;1thinsp;plus;thinsp;lgr;r12thinsp;plus;thinsp;mgr;lpar;r1thinsp;minus;thinsp;r2rpar;2. For He, expectation values other than the energy are typically accurate to four figures.