Section SIEPMANN

• This section specifies the input parameters for the Siepmann-Sprik potential type. Consists of 4 terms: T1+T2+T3+T4. The terms T1=A/rij^alpha and T2=-C/rij^6 have to be given via the GENPOT section. The terms T3+T4 are obtained from the SIEPMANN section. The Siepmann-Sprik potential is designed for water-metal chemisorption.

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

• This section can be repeated.

• This section cites the following reference: [SIEPMANN1995]

• Subsections

  • none

• Keywords

  • ALLOW_H3O_FORMATION
  • ALLOW_OH_FORMATION
  • ALLOW_O_FORMATION
  • ATOMS
  • B
  • BETA
  • D
  • E
  • F
  • RCUT

• Keyword descriptions

  ALLOW_H3O_FORMATION
  	ALLOW_H3O_FORMATION {Logical}
  	The Siepmann-Sprik potential is designed for intact water molecules only. If water is treated at the QM level and an acid is present, hydronium ions might occur. This keyword allows the formation of hydronium ions. The T3 term (dipole term) is switched off for evaluating the interaction between hydronium and the metal.
  	This keyword cannot be repeated and it expects precisely one logical.
  	The lone keyword behaves as a switch to .TRUE.
  	Default value: .FALSE.

  ALLOW_OH_FORMATION
  	ALLOW_OH_FORMATION {Logical}
  	The Siepmann-Sprik potential is actually designed for intact water molecules only. If water is treated at the QM level, water molecules can potentially dissociate, i.e. some O-H bonds might be stretched leading temporarily to the formation of OH- ions. This keyword allows the the formation of such ions. The T3 term (dipole term) is then switched off for evaluating the interaction between the OH- ion and the metal.
  	This keyword cannot be repeated and it expects precisely one logical.
  	The lone keyword behaves as a switch to .TRUE.
  	Default value: .FALSE.

  ALLOW_O_FORMATION
  	ALLOW_O_FORMATION {Logical}
  	The Siepmann-Sprik potential is actually designed for intact water molecules only. If water is treated at the QM level, water molecules can potentially dissociate, i.e. some O-H bonds might be stretched leading temporarily to the formation of O^2- ions. This keyword allows the the formation of such ions. The T3 term (dipole term) is then switched off for evaluating the interaction between the O^2- ion and the metal.
  	This keyword cannot be repeated and it expects precisely one logical.
  	The lone keyword behaves as a switch to .TRUE.
  	Default value: .FALSE.

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

  B
  	B {Real}
  	Defines the B parameter of Siepmann potential
  	This keyword cannot be repeated and it expects precisely one real.
  	Default value: 6.00000000E-001
  	Default unit: [angstrom]

  BETA
  	BETA {Real}
  	Defines the beta parameter of Siepmann potential
  	This keyword cannot be repeated and it expects precisely one real.
  	Default value: 1.00000000E+001

  D
  	D {Real}
  	Defines the D parameter of Siepmann potential
  	This keyword cannot be repeated and it expects precisely one real.
  	Default value: 3.68838800E+000
  	Default unit: [internal_cp2k]

  E
  	E {Real}
  	Defines the E parameter of Siepmann potential
  	This keyword cannot be repeated and it expects precisely one real.
  	Default value: 9.06902500E+000
  	Default unit: [internal_cp2k]

  F
  	F {Real}
  	Defines the F parameter of Siepmann potential
  	This keyword cannot be repeated and it expects precisely one real.
  	Default value: 1.33000000E+001

  RCUT
  	RCUT {Real}
  	Defines the cutoff parameter of Siepmann potential
  	This keyword cannot be repeated and it expects precisely one real.
  	Default value: 3.20000000E+000
  	Default unit: [angstrom]