Section BUCK4RANGES

• This section specifies the input parameters for Buckingham 4 ranges potential type.Functional form: (r<r1) V(r) = A* EXP(-B*r); (r1<r<r2) V(r) = SUM_n POLY1(n)*R^n;(r2<r<r3) V(r) = SUM_n POLY2(n)*R^n; (r>r3) V(r) = -C/r^6

• Section path: CP2K_INPUT / FORCE_EVAL / MM / FORCEFIELD / NONBONDED / BUCK4RANGES

• This section can be repeated and cannot be optional.

• Subsections

  • none

• Keywords

  • A
  • ATOMS
  • B
  • C
  • POLY1
  • POLY2
  • R1
  • R2
  • R3
  • RCUT
  • RMAX
  • RMIN

• Keyword descriptions

  A
  	A {REAL}
  	Defines the A parameter of the Buckingham potential
  	This required keyword cannot be repeated and it expects precisely one real.
  	Default unit: [K_e]

  ATOMS
  	ATOMS {KIND1} {KIND2}
  	Defines the atomic kind involved in the nonbond potential
  	This required keyword cannot be repeated and it expects precisely 2 words.

  B
  	B {REAL}
  	Defines the B parameter of the Buckingham potential
  	This required keyword cannot be repeated and it expects precisely one real.
  	Default unit: [angstrom^-1]

  C
  	C {REAL}
  	Defines the C parameter of the Buckingham potential
  	This required keyword cannot be repeated and it expects precisely one real.
  	Default unit: [angstrom^6K_e]

  POLY1
  	POLY1 C1 C2 C3 ..
  	Coefficients of the polynomial used in the second rangeThis keyword can be repeated several times.
  	This optional keyword can be repeated and it expects a list of reals.
  	Default unit: [K_e]

  POLY2
  	POLY1 C1 C2 C3 ..
  	Coefficients of the polynomial used in the third rangeThis keyword can be repeated several times.
  	This optional keyword can be repeated and it expects a list of reals.
  	Default unit: [K_e]

  R1
  	R1 {REAL}
  	Defines the upper bound of the first range
  	This required keyword cannot be repeated and it expects precisely one real.
  	Default unit: [angstrom]

  R2
  	R2 {REAL}
  	Defines the upper bound of the second range
  	This required keyword cannot be repeated and it expects precisely one real.
  	Default unit: [angstrom]

  R3
  	R3 {REAL}
  	Defines the upper bound of the third range
  	This required keyword cannot be repeated and it expects precisely one real.
  	Default unit: [angstrom]

  RCUT
  	RCUT {REAL}
  	Defines the cutoff parameter of the Buckingham potential
  	This optional keyword cannot be repeated and it expects precisely one real.
  	Default value: 1.00000000E+01
  	Default unit: [angstrom]

  RMAX
  	RMAX {REAL}
  	Defines the upper bound of the potential. If not set the range is the full range generate by the spline
  	This required keyword cannot be repeated and it expects precisely one real.
  	Default unit: [angstrom]

  RMIN
  	RMIN {REAL}
  	Defines the lower bound of the potential. If not set the range is the full range generate by the spline
  	This required keyword cannot be repeated and it expects precisely one real.
  	Default unit: [angstrom]