Investigation of Medium Range Order by Photoemission, Reflectivity, Laser-Induced Crystallization Raman Spectroscopy in Amorphous GeSe2

摘要: It is very difficult to determine the structure of amorphous materials, since long range order completely destroyed, where conventional crystallographic diffraction method becomes less powerful. In many cases, however, infrared1, Raman1 and Mossbauer2 spectroscopies, electro-microscopy are considerably effective means investigate intermediate glasses,3,4 while X ray or neutron methods give important information among near neighbor atoms some suggestions about medium structures. Recent theoretical considerations relate glass forming tendencies global profile structures mean coordination number m. Phillips predicted that formation easiest when m = 2.4. 4,5 Thorpe6 discussed elastic percolation begins at 2.4 in a covalent network glass, if we could sweep means. For several years, we7–12 have investigated composition pressure dependence vibrational spectra g-(Ge,Sn)(Se,S). We paid attention characteristic molecular clusters such as Ge(Se, S)4/2, (Ge1-ySny)(Se, Ge2Se6/2, Sen, S8, Sn. The GeSe4/2 g-GeSe2 highly strained even without external pressure. strain released with increasing selenium x, observed A1 peak, relaxed xc=0.80, 10, 11Such critical behaviors were situations system stability discussed.12, 13