SHELL1

Purpose

An object describing a contracted shell of gaussian functions, including the position of the gaussian

Synopsis

The module consists mainly of a contraction coefficient vector, and exponent vector, an integer describing the "angular momentum" of the shell l = n1 + n2 + n3, where the n are the powers of the cartesian gaussian function, and a position.

This module differes from SHELL in that the position is stored.

The module contains routines for normalisation, and calculating the value of the contracted shell for various functions, such as the kinetic density, or laplacian.

At the moment, only "segmented" cartesian shells are modelled.

The order of the cartesian components is given by routine INT:make_gaussian_xyz_powers. Refer to the online documentation for module INT

Default input data order

There is currently no SHELL1VEC module. However, the data order is defined as:

SHELL1_INPUT_DATA_ORDER     [ l= pos= n_cc= ex,cc= ]

Listing of keywords

cc= REALVEC(n_cc)

Enter a vector of contraction coefficients

  • The value of n_cc must be entered beforehand; see n_cc=

  • Normally modules will assume the coefficients are with respect to normalised gaussian

  • Default units are atomic units

ex= REALVEC(n_cc)

Enter a vector of exponents

  • The value of n_cc must be entered beforehand; see n_cc=

  • Normally modules will assume the coefficients are with respect to normalised gaussian

  • Default units are atomic units

ex,cc= REALVEC(n_cc),REALVEC(n_cc)

Enter alternating vector of exponents and contraction coefficients

  • The value of n_cc must be entered beforehand; see n_cc=

  • Normally modules will assume the coefficients are with respect to normalised gaussian

  • Default units are atomic units

junk,ex,cc= REALVEC(n_cc),REALVEC(n_cc),REALVEC(n_cc)

Enter alternating vector of a junk string, an exponent, and a contraction coefficient

  • The value of n_cc must be entered beforehand; see n_cc=

  • Normally modules will assume the coefficients are with respect to normalised gaussian

  • Default units are atomic units

  • This style is useful for the GAMESS-US program

l= INT|STR

Read either an integer representing the l value of the gaussian; or read a single character representing the angular momentum

  • If the inputted data in an integer, it must be non-negative

  • If the inputted data in a character is must be s, p, d, f, g, ..., z

  • See also l_chr= and l_int=

l_chr= STR

Read a single character representing the angular momentum of the gaussian

  • Must be s, p, d, f, g, ..., z

  • See also l= and l_int=

l_int= INT

Read a single integer which is the angular momentum of the gaussian

  • Inputted data must be non-negative

  • See also l= and l_chr=

n_cc= INT

Enter the number od contractions in this shell

  • This must be enetred before ex= or cc=

  • A shell is a sum of gausian functions; this number is the length of the sum

pos= REALVEC(3)

Enter the position of the center of the shell

put

Print out information about the SHELL1 to the stdout file in human readable form

units= STR

Read a string which describes the units of the next inputted numerical entity; that is, the next real or complex number, real or complex vector, or real or complex matrix.

  • The default atomic units are restored after the numerical entity has been inputted

  • Warning: if the next inputted datum is not a numerical entity, the new units keyword remains in force