Optical Properties of Lattice Vibrations in Molecular Crystals

✍ Scribed by H. Barentzen; B. Schrader; L. Merten

• Publisher: John Wiley and Sons
• Year: 1971
• Tongue: English
• Weight: 506 KB
• Volume: 45
• Category: Article
• ISSN: 0370-1972
• DOI: 10.1002/pssb.2220450213

✦ Synopsis

Abstract

A classical microscopic theory is presented for the optical properties of lattice vibrations in molecular crystals, which are composed of electrically neutral molecules bound by van der Waals forces. It is shown, that Huang's theory, which until now has been applied to ionic crystals only, is also valid for molecular crystals. Finally, oscillator strengths as well as LO and TO frequencies are calculated for thiourea according to the “oriented gas” model. A comparison shows, that the calculated oscillator strengths have the same order of magnitude as those of α‐quartz.