This award by the Solid State Materials Chemistry program in the Division of Materials to Arizona State University is to study theoretical crystal chemistry. This award is a renewal of an earlier one work in developing geometrical basis of crystal chemistry and advances made in understanding the 3-periodic net that underlie crystal structures. The principle goal of this award is the development of a new subdiscipline in chemistry concerned with the taxonomy, geometry and topology of periodic structures, which are important to conventional, and liquid crystals, mesoporous materials etc. Special attention will be devoted to making these results available in a practically usable manner to facilitate the design and subsequent synthesis of materials for which there are pressing needs (e.g. for separations, and for the storage of light gases such as methane and hydrogen). The main components of this award will be: i) Extension of work on enumeration and identification of 3-periodic nets to include nets with vertices of different coordination, and nets with long links, and they included topological analysis of these structures and determination of their natural tilings and their dual structures; ii) Enumeration and study of dual tilings and catenated nets, including systematic study of polycatenated nets; iii) Development and elaboration of the Reticular Crystal Chemistry Structure resource which contains information relative to design and analysis of crystalline materials; and iv) Application of tiling theory to description of complex crystal structures, especially the currently enigmatic intermetallic phases.
Elaboration and enhancement of the data base, Reticular Chemistry Structure Resources, is expected to be a significant open source for many researchers in the design of syntheses, and this data base could be used to develop a library of possible topologies for given combinations of secondary building units of two- and three-periodic nets and polyhedra. The Barrett Honors College program at Arizona State University is expected to continue to support the undergraduate research activities carried out under this project. In addition, the project is expected to continue to support a diverse group of students and scientists consisting of females and African-American, Hispanic-American and other groups.
This research project was devoted to theoretical crystal chemistry, in particular those aspects which lead to the possibility of designed synthesis of new materials with targeted properties. In particular we have found the possible structures for materials made up of two components linked together in a regular )"periodic") way. Such materials are of considerable interest because they can have very open (porous) crystal structures and consequently a large capacity for storing absorbed gas. An immediate application is to clean energy technologies which rely on compact storage of fuel gases such as natural gas and hydrogen. The materials have also great potential for extracting carbon dioxide from the emissions such as flue gases. The main results have been published in major chemical journals. Our results are also available on the internet in a searchable database. The impact of the work can be judged by the publications of the principal investigator (Michael O’Keeffe) are ranked third world-wide in impact (citations of those scientific papers by other scientists), The database created and maintained in this research is currently used annually by more than 10,000 scientist who access more than 100,000 records. Because the methods developed are both new and of wide applicability, there has been considerable demand for short courses 9usuall one week) given by the principal investigator. During this grant period such courses have been given in Germany, Thailand, Vietnam, China, and Korea the project has developed human resources in that several undergraduate science students working on the project have gone on to graduate school and on graduate student (Mexican-American, female) received her. Ph. D. degree and is currently teaching chemistry at arizona State University.
