Crystallographic resources

Instrument sensitivity round robin

The Industrial Group of the BCA are coordinating the UK implementation of an international round robin exercise on Powder Diffraction Sensitivity for the International Centre for Diffraction Data (ICDD). Participants will be required to run a series of 22 scans with varying settings of tube current, voltage, step size, slit size and count times on the NIST standard SRM 1976 Alumina plate. Both Philips and Siemens have donated standards suitable for their sample holders. The study will provide a useful basis for ongoing performance tests to check instrumentation and satisfy the instrument performance criteria of accreditation. The round robin will be launched at the Industrial Group Aummn meeting. For further information contact the UK coordinator: D. J. Taylor, Pilkington Technology Centre, Hall Lane, Lathom, Ormskirk, Lancs L40 5UF, UK. Tel.: 01695 54303, FAX: 01695 54596, e-mail: taylordj@ptc.pilkington.uk.

Heavy Phasing

Version 4 of HEAVY is now available. The "HEAVY" and "HASSP" heavy atom search, refinement, and MIR/MAD phasing programs in an integrated package that runs on a variety of unix and VMS machines. New features of HEAVY include CORRELATED PHASING, BAYESIAN WEIGHTING, and BAYESIAN DIFFERENCE REFINEMENT.

HEAVY is distributed free to non-commercial users. To obtain a license, contact N. Cameron at the Los Alamos Industrial Partnership Office. E-mail: Ncameron@lanl.gov.

1. Specify non-commercial or commercial license.
2. If you are a University of California institution, say so.
3. Your name and e-mail address. If you have an anonymous ftp site, list it.
4. Name and address of person who will sign for your institution.
5. Node name(s) of single site or cluster of computers where HEAVY will be used.

For further information contact T. Terwilliger, e-mail: terwilliger@LANL.gov.

World Directory of Powder Diffraction Programs

The World Directory of Powder Diffraction Programs (WDPDP) is a catalogue of programs available for powder diffraction analysis. It is a joint project of S. Gorter (The Netherlands) and D. K. Smith (USA) and is sponsored by the Commission on Powder Diffraction. The 1995 list of programs contains 670 program listings categorized into 22 areas of activity and 6 subgroups. The directory includes information on the language, platform, distribution and cost, addresses of the program authors and references. E-mail addresses and Fax/Phone numbers are included. The list is maintained and forms are available from S. Gorter to supply program information for additional entries. In addition to the maintenance of the WDPDP, S. Gorter operates the Program Exchange Bank (PEB) where many of the programs in the WDPDP are available on request. Programs may be acquired by ftp or on some specific media. For the latter, fees are charged to cover cost. The cost of the WDPDP itself is US $50 covering printing. mailing (air mail), and currency exchange (cash discount of US $15). Subscribers will receive updates. Payment should accompany orders. An invoice will be enclosed on delivery.

To obtain order forms and place orders: S. Gorter, 43 van Lennepdreef, NL-2353 NJ Leiderdorp, The Netherlands. FAX: 31-71-274537, e-mail: gorter_s@rulgca.leidenuniv.nl.

Acetates Anonymous

Trimethyllead acetate and Triethyllead acetate compounds useful for preparation of heavy atom isomorphs do not seem to be available from major chemical companies. I. Rayment and H. Holden have offered to prepare them for interested colleagues for the cost of materials, time and equipment ($100/g). Those interested in purchasing these chemicals should send checks made payable to the Enzyme Inst., U. Of Wisconsin, to Ivan Rayment. Enzyme Inst., 1710 University Ave, WI 53705, USA.

New Listserve for Crystallographic Announcements

Y. Epelboin has set up a listserv called iucr and WWW page on the server at his institution. This page is at: http://www.lmcp.jussieu.fr/sincris/ under Information Exchange, then International and then Distribution lists. Archives of the list are also accessible there.

Martha Teeter, her husband, CurtissDuRand, and their twins at the Toledo ACA meeting in 1991.

Differences from the past

The address listserv@... administers the list and the address iucr@... for this moderated list goes to M. Teeter. A reply would also go to the moderator.

You can subscribe yourself and sign-off the list by sending to the listserv (listerv@lmcp.jussieu.fr) a message in the body of the mail (not subj:) with one of the following commands:
subscribe listname lastname firstname inst country
signoff listname (iucr)
In case of trouble using the listserv or subscribing/unsubscribing, contact Y. Epelboin at epelboin@lmcp.jussieu.fr.

PARST95 and Auxiliary Programs

The source FORTRAN77 codes of the last release of PARST, a program for the analysis of the geometric aspects of a crystal structure [J. Appl. Cryst. (1995). 28, 659] and some auxiliary programs can be retrieved directly using anonymous file transfer protocol (FTP). The files available are: PARST95.FOR for the analysis of the geometric aspects of a crystal structure, PREP93.FOR for getting the input files to PARST95 and THMV7, from the SHELXL-93 *.lst output file, PARSTCIF.FOR for creating a CIF from the PARST95 output, ORDRIFL.FOR for checking the Laue class and performing a statistical analysis of the extinctions on the data of a *.hkl file, CHANGDAT.FOR for modifying lattice parameters, reflection indices, atomic coordinates and anisotropic displacement parameters according to given rotation matrices and translation vector in the SHELXL-93 *.hkl or *.ins files, or in the PARST95 input file.

The description of what these programs do and how to use them is given as comments at the heads of the source codes.

The procedure to get these files is as follows:
(i) from your work station enter: ftp ipruniv.cce.unipr.it (or ftp 160.78.48.1)
(ii) wait for name, enter: anonymous
(iii) wait for password, enter: (your name)
(iv) wait for ftp >, enter: cd //pub/nardelli
(v) ftp> dir (to have the list of the files)
(vi) ftp> get partst95.for parst95.for
ftp> get prep93.for prep93.for
(vi) ftp> bye (to close)

These codes can be compiled on every machine equipped with suitable compiler. The author will be glad to be informed (e-mail: nardelli@ipruniv.cce.unipr.it) about the success of this retrieving.