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Section &BASIS ...&END

This section specifies the atomic basis used in the properties section or as an initial guess. There have to be number of species different entries in this section. The order of the basis sets has to correspond with the order of the atom types in the section &ATOMS ...&END. With the keyword SKIP the species is skiped and the default minimal Slater function basis is used. Basis sets are either specified as Slater functions or given on an additional input file. The respective input formats are given below.

SLATER   nshell  [OCCUPATION]
  n1   l1    exp1
  ..   ..    ....
  nx   lx    expx
  [f1 f2 ... ]

PSEUDO AO nshell  [OCCUPATION]
  l1   l2   ..   lx     !a function with l=-1 is skipped
  [f1 f2 ... ]

*filename  nshell  FORMAT=f  [OCCUPATION]
  l1   l2   ..   lx
  [f1 f2 ... ]

*filename  nshell  GAUSSIAN  [OCCUPATION]
  l1   l2   ..   lx
  [f1 f2 ... ]

SKIP

The * for the numerical basis has to be in the first column. The default format is 1, other possible formats are 2 and 3. The numbers correspond to the format numbers in the old pseudopotential definitions for the atomic wavefunctions.
The format PSEUDO AO refers to the &WAVEFUNCTION section on the correspondin pseudopotential file. With a L-value of -1 a specific function can be skipped.
The format GAUSSIAN allows to use any linear combination of Gaussian functions. The format of the file is as follows

Comment line
Lmax
(for each l value)
  Comment line
  # of functions; # of exponents
  exp1 exp2 ... expn
  c11  c21      cn1
  c12  c22      cn2
  ...  ...      ...
  c1m  c2m      cnm



Juerg Hutter
Tue Jan 21 09:33:34 MET 1997