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hf

Input files: wfn.inp, optional
Output files: wfn.out
Reference: Froese Fischer C 1987 Computer Phys. Commun. 43 355
  Gaigalas G and Froese Fischer C 1996
  Computer Phys. Commun. 98 255
   

This program has some built-in help features. By entering H (or h) a brief summary of possible responses is provided.

ATOM 1-6 character label for the calculation
TERM $LS$ term value or "AV" or "av" (for average energy)
Z Atomic number, real; non-integers are allowed.
S screening parameter for the orbital
IND   0 - use screened hydrogenic functions as initial estimates
    1 - leave radial function unchanged (already in memory)
  $-1$ - search for function in wfn.inp; otherwise same as 0
ACC accelerating parameter (see HF-acc)
NO maximum number of points in the range of the function ($\le 220$)
STRONG if true, orthogonalize after each orbital update (see HF-strong.
  Enter t for true, f for false
PRINT If t(true) radial functions are printed
SCFTOL initial value of the self-consistency criterion
NSCF the maximum number of SCF cycles.
IC number of orbitals to be updated using the least self-consistent
  criteria.
TRACE If t (true), detailed information about the SCF energy adjust-
  ment process is printed

A feature of the HF program is that the occupation numbers need not be integer. In order to study the $2s - 2p$ transition in Be, for example, orbitals could be computed for the configuration 2s(1.5)2p(0.5) in which case average energy calculations will be performed for

\begin{displaymath}(1/2) \left[ E_{av}(2s^2) + E_{av}(2s2p)\right]\end{displaymath}

Also, various expectation values may be printed at the end of a calculation. A sample input data line is given for each case and, ideally, the input should be aligned with the sample. However, the format for the input is also provided. Here it is helpful to know the following format rules for a line of input.
nX skip n positions on the line (i.e. enter n blanks)
An the next n positions on the line will be interpreted as characters
In the next n positions on the line will be interpreted as an integer

More details can be found in any FORTRAN text.

It should also be remembered that HF is a program for simple cases: if there are two or more open shells, an $LS$ calculation may not be possible using HF. Configurations of the form $nl^w n's$ generally are allowed, $l \le 3$; configurations $np^w n'l$, $l\le 2$ may request information about the parent term for $np^w$; CSFs of the form $nd^w n'l$ are not allowed except for $n'l = n's$; open $f$-shells may have any occupation but, any other open shell may only be single $s$-electron. For more complex situations NONH and MCHF should be used, though these codes have not yet been extended to open $f$-shells.


next up previous contents
Next: levels Up: Utility programs Previous: condens   Contents
2001-10-11