CASINO manual - Theory of Condensed Matter

• Delete any eepot.data and density.data files and regenerate them as a mpc.data file using
the runtype = ‘gen mpc’ option. Alternatively there is a make new mpc utility which will do a
direct conversion.
• The hist update utility should be used to convert old-format vmc.hist, dmc.hist and
dmc.hist2 files to the new-format vmc.hist and dmc.hist files.
• The following changes should be made to the input file (it is probably best to copy an input file
from the new examples and just change the few parameters in the new ‘system-specific’ section
at the top):
1. irun = 1 should be replaced by runtype = ‘vmc’ and use jastrow = F; irun = 2 should
be replaced by runtype = ‘vmc’ and use jastrow = T; irun = 3 should be replaced by
runtype = ‘dmc’; irun = 4 should be replaced by runtype = ‘opt’; irun = 5 or 6 should
be replaced by runtype = ‘gen mpc’.
2. The number of variance-minimization cycles is specified by the opt cycles keyword. A
post-fit VMC calculation will be performed if the postfit vmc keyword is set to T. This
only has effect if the runtype = ‘vmc opt’ or ‘opt vmc’.
3. The keyword opt pairing has been renamed to opt orbitals. Its meaning is unchanged.
4. btype = 7 should be replaced by btype = 4 (and in version 2.1 btype was marked
redundant and replaced by the atom basis tye keyword).
5. The wavefunction block in the input file is no longer used. If you used it to specify
multideterminant or excited-state wave functions then you should move the data to an
‘MDET’ block in correlation.data. The format of the latter is the same as that of the
former except that (i) the ‘MDET’ block has a title (and comment lines introducing the
title and multideterminant data) and (ii) the multideterminant expansion coefficients must
be followed by an integer label and an ‘optimizable’ flag. See Sec. 7.4.4.
6. The keyword energy cutoff has been replaced with separate mpc cutoff and expval
cutoff keywords specifying the cutoff values for the G vector sets used in mpc.data
generation and expectation value accumulation.
7. The keywords denft threshold, dbar tolerance, vm mode, use newjas,
use coeff file and all keywords previously flagged as redundant have been deleted.
8. The keyword use newopt should be removed; to use the ‘newopt’ method (now varminlinjas),
set the keyword opt method to varmin-linjas.
D Appendix 4: Specification of the format of the
correlation.data file
1. The correlation.data file contains: (i) the data specifying the Jastrow factor (the old
jastrow.data); (ii) the data specifying the backflow function (the old backflow.data); (iii) the
data specifying the orbitals occupied in each determinant together with determinant expansioncoefficient
data; (iv) the data specifying the geometry and wave function of electron-gas and
electron–hole-gas systems (these data may be considered to be optimizable parameters). Any
new optimizable parameters, even ones relating to the orbitals specified in xwfn.data, should
be placed in correlation.data.
2. The precise definitions of the Jastrow and backflow data sets are given in Secs. 7.4.2 and 7.4.3,
respectively.
3. If excitation data or determinant expansion-coefficient data are given in correlation.data then
this overrides the ground-state definition given in the xwfn.data file.
4. The correlation.data file uses the following format:
(a) The data should be broken up into ‘sets’. For example, there should be separate sets of
data specifying the Jastrow factor and the backflow function.
(b) Each distinct set of data XXX should begin with a line ‘START XXX’ and end with a line
‘END XXX’.
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