@brief Get first derivative of the XC functional @param[in] xce XC engine @param[in] beta Whether to return spin-polarized quantities @param[out] d_r dE_xc / d_rho (alpha, beta) @param[out] d_s dE_xc / d_sigma (alpha-alpha, beta-beta, alpha-beta) @param[out] d_t dE_xc / d_tau (alpha, beta)
| Type | Intent | Optional | Attributes | Name | ||
|---|---|---|---|---|---|---|
| class(xc_engine_t) | :: | xce | ||||
| logical | :: | beta | ||||
| integer, | intent(in) | :: | ipt | |||
| real(kind=fp), | intent(out) | :: | d_r(2) | |||
| real(kind=fp), | intent(out) | :: | d_s(3) | |||
| real(kind=fp), | intent(out) | :: | d_t(2) |