BUCK4RANGES

Section can be repeated.

This section specifies the input parameters for the Buckingham 4-ranges potential type.

Range	Functional Form
$r<r_1$	$V(r)=A\exp (-Br)$
$r_1\le r<r_2$	$V(r)=\sum _n\mathrm{POLY}1(n)r_n$
$r_2\le r<r_3$	$V(r)=\sum _n\mathrm{POLY}2(n)r_n$
$r\ge r_3$	$V(r)=-C/r_6$

[Edit on GitHub]

Keywords

• A

• ATOMS

• B

• C

• POLY1

• POLY2

• R1

• R2

• R3

• RCUT

• RMAX

• RMIN

Keyword descriptions

A: real = [K_e]

Usage: A {real}

Defines the A parameter of the Buckingham potential [Edit on GitHub]

ATOMS: string[2]

Usage: ATOMS {KIND1} {KIND2}

Defines the atomic kind involved in the nonbond potential [Edit on GitHub]

B: real = [angstrom^-1]

Usage: B {real}

Defines the B parameter of the Buckingham potential [Edit on GitHub]

C: real = [angstrom^6*K_e]

Usage: C {real}

Defines the C parameter of the Buckingham potential [Edit on GitHub]

POLY1: real[ ] = [K_e]

Keyword can be repeated.

Usage: POLY1 C1 C2 C3 ..

Coefficients of the polynomial used in the second range This keyword can be repeated several times. [Edit on GitHub]

POLY2: real[ ] = [K_e]

Keyword can be repeated.

Usage: POLY2 C1 C2 C3 ..

Coefficients of the polynomial used in the third range This keyword can be repeated several times. [Edit on GitHub]

R1: real = [angstrom]

Usage: R1 {real}

Defines the upper bound of the first range [Edit on GitHub]

R2: real = [angstrom]

Usage: R2 {real}

Defines the upper bound of the second range [Edit on GitHub]

R3: real = [angstrom]

Usage: R3 {real}

Defines the upper bound of the third range [Edit on GitHub]

RCUT: real = 1.00000000E+001 [angstrom]

Usage: RCUT {real}

Defines the cutoff parameter of the Buckingham potential [Edit on GitHub]

RMAX: real = [angstrom]

Usage: RMAX {real}

Defines the upper bound of the potential. If not set the range is the full range generate by the spline [Edit on GitHub]

RMIN: real = [angstrom]

Usage: RMIN {real}

Defines the lower bound of the potential. If not set the range is the full range generate by the spline [Edit on GitHub]