CASINO manual - Theory of Condensed Matter
CASINO manual - Theory of Condensed Matter
CASINO manual - Theory of Condensed Matter
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points to be used (1000 is a good bet); for pwscf the number <strong>of</strong> points is given in the pw2casino.dat<br />
file (the keyword ‘n points for test’).<br />
Finally, blip will ask you whether you wish to calculate the kinetic energies <strong>of</strong> your orbitals (in the<br />
plane-wave and blip representations). Obviously, the kinetic energies should be in good agreement.<br />
This test can take some time to run, however, and is <strong>of</strong>ten skipped.<br />
When casino is run, the formatted bwfn.data file is converted into the unformatted and much<br />
smaller bwfn.data.bin file. If you update the formatted bwfn.data file then please be sure to<br />
delete the bwfn.data.bin file(s); otherwise the bwfn.data.bin file(s) will be read and the (updated)<br />
bwfn.data file will be ignored.<br />
An older format binary blip file—bwfn.data.b1—is still supported. Note that pwscf can bypass the<br />
conversion to binary step in casino, as it is capable <strong>of</strong> producing single bwfn.data.b1 files directly<br />
(in fact, it does this by default). It is intended that pwscf will presently be converted to produce<br />
.bin files instead <strong>of</strong> .b1, and by the time you read this, that may have already been done.<br />
If your machine has CPUs with multiple cores, the set <strong>of</strong> blip (or Gaussian) coefficients can be shared<br />
among the cores in each CPU, thus saving a significant amount <strong>of</strong> memory. This feature, which<br />
is implemented for both unix System V Inter-Process Communication and POSIX shared memory,<br />
must be enabled at compile-time by setting in the relevant Makefile include files the flags NEED SHM to<br />
yes and CPP FLAGS SHM to -DSHM SYSV or -DSHM POSIX for System V or POSIX version, respectively.<br />
(Once set up correctly. Just type ‘make shm’ or ‘make openmpshm’.)<br />
The gain in speed with respect to plane waves should be <strong>of</strong> the order <strong>of</strong> N PW /64, where N PW is the<br />
number <strong>of</strong> plane waves in the plane-wave basis.<br />
Localized plane-wave orbitals can also be represented in terms <strong>of</strong> blips, using the blip conversion<br />
utility. This is discussed in Sec. 27.<br />
10 Utilities provided with the <strong>CASINO</strong> distribution<br />
A large variety <strong>of</strong> little programs which do useful things are provided in the ~/<strong>CASINO</strong>/utils/ directory.<br />
Although you should probably refer to the README files in each <strong>of</strong> the subdirectories for<br />
up-to-date and more comprehensive information, here we provide a reasonably current list <strong>of</strong> them:<br />
• abinit to casino pp, casino to abinit pp: Converts pseudopotentials for the abinit program<br />
into casino format, and vice versa.<br />
• billy: Shell script for optimizing basis sets and geometrical parameters with crystal95/98/03/06/09.<br />
Reasonably vital for developing decent trial wave functions for casino<br />
with these programs. See the documentation in ~/<strong>CASINO</strong>/utils/billy/ (this was the first<br />
proper computer program that baby MDT ever wrote). The opt crystal utility is a more<br />
modern version <strong>of</strong> this and is normally to be preferred.<br />
• blip: Utility to read in a pwfn.data file and produce a bwfn.data file. See Sec. 9 for further<br />
information.<br />
• casinohelp: Simple script to invoke the casino help system. Usage:<br />
casinohelp <br />
casinohelp search <br />
casinohelp all<br />
casinohelp basic<br />
casinohelp inter<br />
casinohelp expert<br />
: tells you the definition and type <strong>of</strong> keyword<br />
: finds in descriptions <strong>of</strong> all keywords<br />
: lists all possible keywords<br />
: lists all basic level keywords<br />
: lists all intermediate level keywords<br />
: lists all expert level keywords<br />
• champ to casino pp: Converts pseudopotentials for the champ QMC program into casino<br />
format.<br />
• clearup: Script for cleaning up after casino by removing output and indicator files, etc. It<br />
attempts to ‘reset’ directories to a suitable starting point.<br />
• clearup twistav: Script for cleaning up after a twist-averaging calculation using<br />
twistav pwscf or twistav castep.<br />
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