SOFTWARE/DATABASE UPDATE
Metallated polymer for molecular wire
SAN FRANCISCO Imagine a string of metal atoms, each atom anchored to a flexible polymer backbone that also serves as an insulat ing sheath. Such a "molecular wire" might one day be used to connect elec tronic components in nanoscale devices. At least thafs the dream of Clifford P. Kubiak, a chemistry professor at Purdue University, who presented his results to the Division of Inorganic Chemistry. Ku biak is trying to develop such a molecu lar wire using poly(l-phenyl-l-phosphabutylene) or [P(C6H5)CH2CH2CH2]n as a support. He and graduate student Jean C. Huang have discovered a sim ple, one-step synthesis for the polymer that requires no solvent. The polymer can be dissolved in many common organic solvents. Once in solution, it can be reacted with a pentacarbonyl tungsten complex. The result is that one W(CO)5 group attaches to each phosphorus atom on the chain. The spacing of the phosphorus atoms (every fourth atom of the chain) is such that the tungsten atoms form a potentially con ducting path along the chain. This metallated polymer also is solu ble in organic solvents. Thaf s a key re quirement, in fact, because Kubiak be lieves a true molecular wire must be able to withstand the type of chemical ma nipulations and processing that chemists routinely carry out on molecules. In preliminary experiments, Kubiak and Huang have so far synthesized polymer strands carrying as many as 15 tungsten atoms in a row. Before electrical conductivity mea surements can be made, though, longer wires will have to be prepared. The polymer will have to be doped to b e come conductive, and the carbonyls re moved to allow formation of tungstentungsten bonds. And both ends of the polymer chain will have to be functionalized and coordinated to metal elec trode surfaces. Obviously, much still needs to be done, but Kubiak is hopeful that this approach will work. Ron Dagani
• Dictionary of Fine Chemicals (Chemical Design, yearly subscrip tion $16,000 and up, Circle 301) is a database of 3-D structures and as sociated information on small or ganic compounds, including aromatics and heterocycles. The struc tures are based on a 2-D database compiled by British publisher Chap man & Hall. The program is avail able in versions for IBM PCs, Macin toshes, VAXes, and UNIX worksta tions. • Balance-Mate (Software Excel lence, $149, Circle 302) interfaces Mettler, Sartorius, and other brands of electronic balances to IBM PCcompatible computers.
• ChemWords, Bio/Chem Words, and BioWords (Scientific Software; $75, $125, and $75, respectively; Cir cle 308), for the IBM PC, are supple mentary scientific dictionaries for WordPerfect 5.1, each containing tens of thousands of words. • Easy Jersey 2.0 (Softrak Systems, $120, Circle 309) is a hazardous chemicals database and labeling program for IBMs and compatibles. It includes the New Jersey hazard ous chemicals database, as well as chemical searching and right-toknow labeling capabilities.
• DAQ Designer (National Instru ments, free, Circle 303) helps config ure data acquisition systems for IBM PC-compatible computers. It prompts users for system requirements, ana lyzes answers, and recommends hardware and software.
• ExQC (Automated Technology Associates, $120,000 site license, Cir cle 310) is an exploratory quality control system that allows process improvement teams to isolate, d e fine, and solve manufacturing quali ty problems. The UNIX- and DECbased software evaluates relation ships among data from multiple process and product systems.
• ChemPrint (Tripos Associates, pricing upon request, Circle 304) is a Windows-based scientific desktop publishing program for IBM PCs. It incorporates text and images of chemical structures and reaction di agrams into scientific papers and re ports.
• SigmaPlot 5.0 (Jandel Scientific, $495, Circle 311), a new version of the SigmaPlot technical graphing program, makes it possible to create and rotate plots in three dimensions using commands similar to those used in previous two-dimensional versions.
• Chaos Demonstrations 2.0 (Phys ics Academic Software, $70, Circle 305) has been expanded from the previous version with new exam ples of chaotic events, including 13 three-dimensional animations that are viewed with 3-D glasses. It runs on IBM PCs.
LITERATURE
• PDLCOM (Plastics Design Li brary, $399, Circle 306) is an IBM PC-based source of reference data on the effects of different exposure environments on the physical char acteristics of plastics. • Maple V: Student Edition (Brooks/Cole Publishing, $99, Circle 307), an algebra program that ma nipulates, solves, and graphs mathe matical equations, is available for Macintosh and IBM 386 and 486 computers. It includes more than 1700 built-in mathematical func tions.
Μ Molecular Modeling and Compu tational Chemistry Results (MMCC Publishing, $295 annual subscrip tion, Circle 312), published 10 times a year, organizes and provides brief summaries on research papers from scientific journals. The reviews, which range from a sentence to a paragraph in length, emphasize r e suits obtained and methods em ployed. • "Scientific Software Catalog 1992" (Europa Scientific Software, free, Circle 313) is a 60-page catalog of over 200 software packages for the IBM PC and the Macintosh from more than 60 different scientific soft ware developers. • For information on these items see Reader Service Card APRIL 20,1992 C&EN 27
