Relativistic exchange-correlation energy functional: Gauge dependence of the no-pair correlation energy
نویسندگان
چکیده
We analyze the gauge dependence of the relativistic electron gas correlation energy Ec resulting from the no-pair approximation. In particular, we evaluate the relativistic no-pair Lindhard function as the basic ingredient of the random-phase approximation ~RPA! for Ec . The resulting gauge-dependent no-pair RPA is compared with a gauge-invariant counterpart. The implications for relativistic density functionals are examined by applying the local-density approximation based on each of these forms of Ec to atoms. It is found that the gauge dependence of Ec is irrelevant on the overall level of accuracy obtained with present density functionals. @S1050-2947~98!07207-2#
منابع مشابه
Relativistic correlation
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