MMAE Seminar - Growth and Application of New Solution-grown Organic Crystals
Armour College of Engineering's Mechanical, Materials & Aerospace Engineering Department will welcome Dr. Natalia Zaitseva, Distinguished Member of Technical Staff of Lawrence Livermore National Laboratory, on Wednesday, September 30th to present her lecture, Growth and Application of New Solution-grown Organic Crystals*.
Abstract
Low-temperature solution growth is the simplest, and in many cases, the least expensive method for production of optical crystals. However, its use for growth of large, commercially important single crystals has been so far limited to a few inorganic water-soluble materials, examples of which include Rochelle salt, triglycine sulphate, or potassium dihydrogenphosphate (KDP). For organic crystals, not soluble in aqueous solutions, the preference has been given to alternative methods, among which the Bridgman technique is the most common. Modern availability of commercially produced high-purity organic solvents and recent development of accelerated techniques for solution growth enables wider variations of growth methods to produce crystals of different materials. When large volumes of single crystal materials are needed for certain applications, solution growth methods may offer the advantage of easier scale-up. For organic crystals, one such application relates to their use in scintillation devices that deploy fluorescent properties of organic crystals enabling efficient neutron detection in the presence of gamma radiation. The presentation will describe growth of large (~10 cm scale) single crystals of pure aromatic hydrocarbons, trans-stilbene, 9,10-diphenylanthracene, diphenylacetylene, and bibenzyl, as well as crystals of aromatic compounds containing metal atoms (Li, Cs) in their composition. Growth mechanisms and measures to prevent specific defect formation will be discussed to show that under controlled conditions solution growth produces crystals of higher structural perfection and better optical quality in comparison to the same crystals grown by traditional melt techniques. With large variety of unexplored organic crystals, the results of the studies indicate new pathways for production of novel materials for different applications.
Lawrence Livermore National Laboratory is operated by Lawrence Livermore National Security, LLC, for the U.S. Department of Energy, National Nuclear Security Administration under Contract DE-AC52-07NA27344. This work has been supported by the U.S. Department of Energy NA-22, and by the US Department of Homeland Security, DNDO, under competitively awarded IAA HSHQDC-09-X-00743. This support does not constitute an express or implied endorsement on the part of the Government.
* The research was performed in collaboration with Leslie Carman, Andrew Glenn, Andrew Mabe, and Stephen Payne.
Biography
Ph.D. in Physics and Mathematics from Moscow State University. In 1993 Dr. Zaitseva joined Lawrence Livermore National Laboratory to lead scientific development of rapid growth technology for large-scale (>50 cm) KDP and DKDP crystals for the National Ignition Facility (NIF). Dr. Zaitseva is currently the PI for projects on development of new classes of organic scintillator materials for radiation detection funded by DHS/DNDO, and DOE NA-22 and DTRA offices. She and her team conducted extensive survey and studies of organic materials capable of neutron/gamma Pulse Shape Discrimination (PSD). The results led to discovery of new single crystal organic scintillators and first plastic scintillators with efficient PSD, transferred to industry for commercial production.
Dr. Zaitseva received worldwide recognition for her work in studies and development of new materials. She is a recipient of the International Robert Laudise Award in crystal growth (2010), two100 R&D awards for the development of Rapid growth technology for production of large-scale crystals (1994) and first PSD plastic scintillators for neutron detection (2012), numerous LLNL Directorate awards (1994-2013), and DNS/DNDO award for development of new crystals for radiation detection. She is an author of more than 80 publications and 9 patents.