38 lines
990 B
Fortran
38 lines
990 B
Fortran
double precision function mu_rs_c(rho)
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implicit none
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double precision, intent(in) :: rho
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include 'constants.include.F'
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double precision :: cst_rs,alpha_rs,rs
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cst_rs = (4.d0 * dacos(-1.d0)/3.d0)**(-1.d0/3.d0)
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alpha_rs = 2.d0 * dsqrt((9.d0 * dacos(-1.d0)/4.d0)**(-1.d0/3.d0)) / sqpi
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rs = cst_rs * rho**(-1.d0/3.d0)
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mu_rs_c = alpha_rs/dsqrt(rs)
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end
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double precision function mu_grad_rho_func(r)
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implicit none
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double precision , intent(in) :: r(3)
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integer :: m
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double precision :: rho, dm_a, dm_b, grad_dm_a(3), grad_dm_b(3)
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double precision :: eta, grad_rho(3), grad_sqr
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eta = mu_erf
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call density_and_grad_alpha_beta(r,dm_a,dm_b, grad_dm_a, grad_dm_b)
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rho = dm_a + dm_b
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do m = 1,3
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grad_rho(m) = grad_dm_a(m) + grad_dm_b(m)
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enddo
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grad_sqr=0.d0
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do m = 1,3
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grad_sqr=grad_sqr+grad_rho(m)*grad_rho(m)
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enddo
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grad_sqr = dsqrt(grad_sqr)
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if (rho<1.d-12) then
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mu_grad_rho_func = 1.d-10
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else
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mu_grad_rho_func = eta * grad_sqr / rho
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endif
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end
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