Notes and News Groups and Generates the Required This Section Is Intendeed to Be a Series of Short Para- Symmetry Instructions for ORTEX

COMPUTER PROGRAM ABSTRACTS 439 in the SHELX file for all space Crystallographers Notes and News groups and generates the required This section is intendeed to be a series of short para- symmetry instructions for ORTEX. graphs dealing with the activities of crystallographers, J. Appl. Cryst. (1994). 27, 439-440 ORIN generates instructions for 'long' such as their changes of position, promotions, as- bonds, can translate the asymmetric sumption of significant new duties, honours etc. Items The new high-resolution neutron powder for inclusion, subject to the approval of the Editorial unit and can append unit-cell corners Board, shouldbe sent to The Executive Sectretary, 2 diffractometer (HRNPD) is now available to the atom list. A 'fast' colour-coded Abbey Square, ChesterCH1 2HU, England. at the Brookhaven high-flux beam reac- stick rotator is provided to allow rapid tor (HFBR). This new user facility offers view selection. ORTEX will generate resolution in neutron powder diffraction drawings of this view with many options. J. AppL Cryst. (1994). 27, 439 patterns exceeding that of many 'home Some of the options are: bonds only, laboratory' X-ray diffractometers in the bonds and atom outlines, bonds and Professor Anthony Kevin Cheetham, high-angle region where the highest thermal ellipsoids and bonds with atom Director of the Materials Research Lab- peak densities usually occur. First outlines and atom-centred numbering in oratory at the University of California operated on 1 July 1993, the HRNPD two print sizes. Any view may be rotated at Santa Barbara, USA, and Professor has an instrumental profile that is smooth on any of x, y and z in any order. Any of Solid State Chemistry in the Royal and nearly symmetric as well as narrow. drawing may be written to a plot file. Institution, London, was elected a Fel- To combine high resolution with high Standard VGA is the default screen low of the Royal Society on 10 March intensity, the unit features a 25-element mode and three SVGA modes up to 1994. He was distinguished for his work 'Venetian-blind' monochromator design 1280 x 1028 are available. The 800 x on determining the chemical structure of and 64 3He detectors. 600 mode works on most machines and materials, especially inorganic materials. As is shown by the 420 reflection of the higher modes work best on VESA He has developed and exploited neu- CeO2 below, the FWHM of the instru- machines. All screen modes use a black tron beams and synchrotron radiation, mental profile is no more than 0.15 ° background and two options that include especially powder profile methods to an- at 103 ° (20) with 11 '-11 '-5' collimators a title are suitable for making slides. alyse the structure of solid-state materi- in place. This corresponds to (Jd)/d in If the unit cell is appended by ORIN, als not amenable to single-crystal X-ray the 10-4 range. With this unusually high the cell outline can be drawn. This is and spectroscopic techniques. This has resolution and an excellent flux on spe- colour coded to allow easy identification enabled him to interpret the behaviour of cimen (e.g. 3 x 105 neutrons cm -2 s -1 of the origin and the a, b and c directions. microporous catalysts and adsorbers, of with the HFBR operating at half power), Two lattice-packing modes are provided. great potential industrial value. the HRNPD takes a leading place among Simple application of the space-group the neutron powder diffractometers of operations to asymmetric units in one the world. Many studies dependent or more cells can be used to examine Professor George Guy Dodson, Profes- on details of the reflection profiles the crystal lattice; a cell-fill mode is also sor of Biochemistry in the University of (e.g. slight splitting from subtle phase provided. In cell-fill mode, the program York and Head of the Division of Protein changes, correct separation of the attempts to fill one or more unit cells with Structures at the National Institute for contributions from different phases, asymmetric units. Medical Research, was elected a Fel- microstructure studies via details of 'line' Colour or black-and-white files may low of the Royal Society on 10 March broadening) are now made possible. be written in HPGL or for the DeskJet 1994. He is renowned for performing series of plotters. The HPGL files may X-ray analyses of numerous biological be printed on LaserJet III or 4 or inserted substances in order to determine their into a drawing package. structure and form. He has undertaken a Inlens~ty (coun() major study on insulin in different forms, 14(3 Hardware environment: The program both naturally occurring and man made. 12C requires at least a 386/387, DOS 5, He has also undertaken extensive in- 10(: 4 Mbytes of RAM, a VGA screen and vestigations into bacterial genetic mate- 8C about 3 Mbytes of disk space. rial and into haemoglobin. His laboratory 6C

solves the structures of crystalline pro- 4C teins from all over the world. Documentation and availability: The 2C .....-..-_._ program, together with manual and i test files is available on 1.44 Mbyte Professor James Fraser Stoddart, floppy disks or via ftp from the author, 102 8 1030 103.2 1034 1036 103 8 Professor of Organic Chemistry in the 2e {degrees) IN%P.McArdle@ UCG.IE. (420) reflectlo~ of CeO2 University of Birmingham, was elected a Fellow of the Royal Society on 10 420 reflection of CeO2 Keywords: Crystallography; ORTEP; March 1994. He was distinguished SHELX; PC; protein; PDB; unit cell; plot for the design and discovery of new The HRNPD is being operated as a file. approaches to the synthesis of novel national/international facility by a PRT organic substances using the tech- (participating research team) to which niques of molecular recognition and is allocated 50% of the instrument's References supramolecular chemistry. He combined time. The other 50% is now available to Johnson, C. K. (1971). ORTEP. Report a number of techniques from synthetic general users on a competing proposal ORNL-3794 revised. Oak Ridge Na- chemistry to establish the principles of basis. There is no charge for using it for tional Laboratory, Tennessee, USA. self-assembly and template direction research work that is neither proprietary Sheldrick, G. (1993). SHELXL-93. in organic synthesis. His work opens up nor for commercial gain. One may gain Program for the Refinement of Crys- the possibility of novel chemical sensors. access to the instrument either as a tal Structures. Univ of G6ttingen, It has created completely new areas of general user or, on occasion, through Germany. experimental inquiry in organic chemistry collaboration with a PRT member. For a McArdle, P. (1993). J. Appl. Cryst. 26 and the investigation of new organic General User Proposal Form, write to Ms 752. materials. Rae Greenberg, HFBR User Program 440 NOTES AND NEWS

Administrator, Physics Department, J. AppL Cryst. (1994). 27, 440 Book Reviews Brookhaven National Laboratory, Upton, NY 11973, USA. For a list of PRT Efficient SHG/THG Generation of Works intended for notice in this column should be sent direct to the Book-Review Editor (R. F. Bryan, members and their addresses, contact Ultrafast Lasers Professor R. A. Young, PRT Chairman Department of Chemistry, University of Virginia, McCormick Road, Charlottesville, Virginia 22901, for the HRPND, School of Physics, An all-reflective second- and third- USA). As far as practicable, books will be reviewed in Georgia Institute of Technology, Atlanta, harmonic-generation system is now a country different from that of publication. GA 30332, USA. available from INRAD for use with ultrafast -I-i:sapphire lasers. Model 5-050 J. AppL Cryst. (1994). 27, 440-441 features a compact reflective design to minimize pulse distortion due to The Rietveld method. (IUCr Mono- chromatic aberration and group-velocity dispersion that typically are found in graph on Crystallography, No. 5.) lens-based systems. A precision optical Edited by R. A. Young. Pp. x + delay, polarization-altering optics and 298. Oxford: International Union of New Commercial Products crystals are all contained in one compact Crystallography/Oxford University package. A selection of crystals and Press, 1993. Price £45.00. ISBN Announcements of new commercial products are pub- optics is available to maintain either lished by the Journal of Applied Crystallography free 0-19-855577-6. of charge. The descriptions, up to 300 words or the fs or ps pulse durations with efficient equivalent if a figure is included, should give the price SHG from 350 to 450 nm and THG from and the manufacturer's full address. Full or partial 233 to 300 nm. Typically, 100 mW of inclusion is subject to the Editor's approval and to the In 1969, H. M. Rietveld published space available. All correspondence should be sent to average THG power can be obtained his seminal paper on structure refine- the Editor, Dr A. M. Glazer, Editor Journal of Applied while maintaining a THG pulse duration ment based on the complete powder Crystallography, Clarendon Laboratory, University of of 200 fs, as shown by cross-correlation diffraction profile rather than a limited Oxford, Parks Road, Oxford OX1 3PU, England. measurements of the third harmonic The International Union of Crystallography can as- amount of low-angle integrated intensity sume no responsibility for the accuracy of the claims and fundamental with an INRAD model data. This paper laid the foundation made. A copy of the version sent to the printer is sent 5-14BX computerized autocorrelator. to the compny concerned. for a dramatic renaissance of powder diffraction, widely regarded at the INRAD, 181 Legrand Avenue, Northvale, time as a valuable tool for phase NJ 07647, USA. J. Appl. Cryst. (1994). 27, 440 identification and qualitative analysis but of little use for quantitative structure Mirror Optics determination. The coming-of-age of Rietveld refinement, as it is now known, The Molecular Structure Corporation was celebrated in June 1989 at an (MSC) has introduced a high-perform- J. Appl. Cryst. (1994). 27, 440 International Workshop on the Rietveld ance focusing mirror system that Method, hosted by the Netherlands produces a three- to fourfold improve- Energy Research Foundation at Ri- ment in .flux relative to a standard Cold Probe etveld's home institution in Petten graphite monochromator. The system The new FC55 immersion cooler and organized by the Commission on is completely integrated with the Rigaku generates temperatures down to -55°C Powder Diffraction of the International R-AXIS imaging-plate system and rotat- using non-CFC refrigerant gas in a Union of Crystallography. ing-anode source. It is easily coupled reliable mechanical refrigeration system. The Rietveld method is an outcome of with the R-AXIS 28 stage developed by The FC55 can be used in place of the Petten meeting but is certainly not a MSC. It is also sold as a stand-alone dry ice or liquid nitrogen as a cooling Proceedings in the accepted sense. The unit. Diffraction experiments requiring source for liquid baths or as a cold contributing authors, all of them leaders a high-flux fine-focus X-ray source will trapping surface to trap solvents or other in the field, were requested to write arti- benefit from this device. condensates from vapor streams. The cles suitable for a book aimed primarily The double-focusing mirror optics as- FC55 generates cooling power of more at those with some experience of the sembly is enclosed in an He-filled cham- than 230 BTU h -1 at -40°C and has a technique but also providing some intro- ber with leaded glass front for safe view- footprint of only 10.5 in wide x 16.5 in ductory material for beginners. The first ing during alignment. The optics consist deep. drafts of these chapters underwent con- of a Pt-plated 160 mm focusing mirror. siderable revision under the guidance Both mirrors have a remote control for and encouragement of the editor and the translation, bending and slit insertion. A end result is not only an authoritative fluorescent screen and attenuators are and coherent text but also an excellent also enclosed in the He-filled chamber, reference work covering the literature up which can be changed by a remote se- to the start of 1991 or thereabouts. lection switch. The collimator is attached The first chapter (R. A. Young) to a high-precision xy assembly. provides an excellent introduction to the The system was designed to be easy Rietveld method. It contains an account to align, generally taking less than of the basic mathematical procedures 30 min. The alignment is unique in that used in the fitting to the diffraction it starts with the mirror nearest the X-ray pattern, the types of parameters to source and proceeds component by be refined, a list of the peak-shape component all the way to the alignment functions commonly used, corrections of the ~ axis. for preferred orientation (one of the more The FC55 cold probe troublesome systematic errors afflicting Molecular Structure Corporation, 3200 X-ray powder data), some of the popular Research Forest Drive, The Woodlands, FTS Systems, Inc., PO Box 158, Rt 209, computer programs currently available, TX 77381, USA. Stone Ridge, NY 12484, USA. criteria of fit and precision and accuracy,