mbd_damping Module

Damping functions.

Contents

Derived Types

damping_t

Functions

damping_fermi

Derived Types

type, public :: damping_t

Represents a damping function.

Components

Type	Visibility	Attributes		Name		Initial
character(len=20),	public		::	version
real(kind=dp),	public		::	beta	=	0d0
real(kind=dp),	public		::	a	=	MBD_DAMPING_A
real(kind=dp),	public		::	ts_d	=	TS_DAMPING_D
real(kind=dp),	public		::	ts_sr	=	0d0
real(kind=dp),	public		::	mayer_scaling	=	1d0
real(kind=dp),	public,	allocatable	::	r_vdw(:)
real(kind=dp),	public,	allocatable	::	sigma(:)
real(kind=dp),	public,	allocatable	::	damping_custom(:,:)
real(kind=dp),	public,	allocatable	::	potential_custom(:,:,:,:)

Type-Bound Procedures

procedure, public :: set_params_from_xc => damping_set_params_from_xc

Functions

public function damping_fermi(r, s_vdw, d, df, grad) result(f)

$$\begin{gathered} f_{(ij)}=\frac1{1+\exp\big({-}a(\eta-1)\big)},\qquad \eta=\frac{R_{(ij)}}{S_{\text{vdW}(ij)}}\equiv \frac{R_{(ij)}}{\beta R_{\text{vdW}(ij)}} \\ \frac{\mathrm df}{\mathrm dR_c}= \frac a{2+2\cosh\big(a(\eta-1)\big)}\frac{\mathrm d\eta}{\mathrm dR_c},\qquad \frac{\mathrm d\eta}{\mathrm dR_c}= \frac{R_c}{RS_\text{vdW}}- \frac{R}{S_\text{vdW}^2}\frac{\mathrm dS_\text{vdW}}{\mathrm dR_c} \end{gathered}$$

Arguments

Type	Intent	Optional	Attributes		Name
real(kind=dp),	intent(in)			::	r(3)
real(kind=dp),	intent(in)			::	s_vdw
real(kind=dp),	intent(in)			::	d
type(grad_scalar_t),	intent(out),	optional		::	df
type(grad_request_t),	intent(in),	optional		::	grad

Return Value real(kind=dp)