CASINO

The Cambridge quantum Monte Carlo code

CASINO is a code for performing quantum Monte Carlo (QMC) electronic structure calculations for finite and periodic systems. Its development was inspired by a Fortran 77 development code (known simply as 'the QMC code') written in the early 1990s in Cambridge by Richard Needs and Guna Rajagopal, assisted by many helpful discussions with Matthew Foulkes. This was later extended by Andrew Williamson up to 1995 and then by Paul Kent and Mike Towler up to 1998. Various different versions of this program were able to treat FCC solids, single atoms and the homogeneous electron gas. By the late 1990s it was clear that a modern, general code capable of treating arbitrary systems (at least atoms, molecules, polymers, slabs, crystals and electron phases) was required, not only for the use of the Cambridge QMC group, but for public distribution. At that time, a sufficiently general, user-friendly, publicly available code did not exist, and it was felt to be a good thing to create one to allow people around the world to join in the fun.

So, beginning in 1999, a new Fortran 90 code - CASINO - was gradually developed in the group of Richard Needs largely by Mike Towler, considerably assisted from 2002 by Neil Drummond and from 2004 by Pablo López Ríos. Some routines from the old code were retained, translated and reused, although most were gradually replaced. The main aims of the new code were generality, speed, ease-of-use and transferability over a wide range of computational hardware. It is hoped that these objectives have largely been attained, but the code continues to be actively developed.

Over the years, additional contributions have been made by D. Alfè, R.Q. Hood, Z. Radnai, A. Badinski, L. Anton, A.R. Porter, C. Pickard, G. Rajagopal, A. Ma, R. Maezono, R. Gaudoin, J.R. Trail, N.Hine, P.R.C. Kent, A.J. Williamson, B. Wood, G.J. Brown, M.D. Brown, K. Esler, A.J. Morris, N. Nemec, R.M. Lee, P. Seth and possibly others, for which we are grateful.

The citation required in any publication quoting results obtained with the current version of CASINO is as follows:
R.J. Needs, M.D. Towler, N.D. Drummond and P. López Ríos, J. Phys.: Condensed Matter 22, 023201 (2010).

Note that in order not to offend Italian speakers we prefer to stress the final syllable and write the name of the program as CASINÒ, but clearly the user will be the final judge of whether this modification is justified.

The code is normally made available on request subject to certain conditions of use enforced by the user signing an agreement. No payment is requested from academic users wishing to use the code for non-profit making purposes (but of course we appreciate any donations.). Profit-making bodies/commercial companies should make a specific enquiry about availability and conditions. Due to the large volume of enquiries and support requests, and a shortage of staff to deal with them, we find it difficult to help new users as much as we would like when they are learning how to use the code. It is recommended instead that potential users attend one of our CASINO summer schools in our monastery in Tuscany which are held every summer.

If you are happy with the above and wish to obtain a copy of the code, then please email Mike Towler (mdt26 at cam.ac.uk) outlining briefly the nature of your interest. You should also send a signed copy of the agreement for each potential user of the code (or this slightly modified agreement for the managers of computer centres/large multi-user machines) either by fax (+44 (0)1223 337356) or regular mail (to Prof. R.J. Needs, TCM Group, Cavendish Laboratory, J.J. Thomson Ave., Cambridge CB3 OHE). Please note that if you are a Ph.D. student you should also get your Ph.D. supervisor to write to us and to sign an additional form. Please also note that because of Professor Needs's age he often forgets to give Mike any signed agreement forms he gets faxed (usually he stuffs them in a drawer) so the accompanying email to Mike Towler is usually essential if you actually want to get a copy of the code.