dc.creator Johnson, Bruce R. en_US dc.creator Simpson, William T. en_US dc.date.accessioned 2006-06-15T13:50:43Z dc.date.available 2006-06-15T13:50:43Z dc.date.issued 1976 en_US dc.identifier 1976-TR-4 en_US dc.identifier.uri http://hdl.handle.net/1811/9878 dc.description $^{1}$ A. Gatterer, G. Piccardi, and F. Vincenzi, Ricerche Spettr. Lab. Astrofis. Specola Vaticana 1, 181 (1942). $^{2}$ R. F. Barrow and A. H. Chojnicki, J. C. S., Faraday Trans. II, 71 (4), 728 (1975). en_US dc.description Author Institution: Department of Chemistry, University of Oregon en_US dc.description.abstract Metallic reflection occurs in molecular crystals when a stopping band, associated with a strong molecular electronic transition, emerges. There are interesting variations in reflectivity over the band, and we report here a calculation of the reflection bandshape for two specific cases -- 1,5-bis-(dimethylamino)pentamethinium perchlorate (BDP) and tetracyanoquinodimethane (TCNQ). Variations in reflectivity are described by a frequency dependent damping term $\Gamma (\omega)$ in the expression for the polarizability. For the case of one molecule per unit cell (BDP), the observed reflection bandshape can be matched using a theoretical expression $\Gamma (\omega)=(\gamma^{2}/N)\Sigma_{k} 1/(\omega-\omega_{k}-\Delta)$ where $\gamma$ is the single molecule vibrational relaxation constant and $\Delta$ is the frequency of the active vibration. For the more complicated case of two molecules per unit cell (TCNQ) a similar theoretical expression predicts a reflection spectrum much richer in structure than in the case of one molecule per unit cell, which moreover, is in substantial agreement with the observed spectrum of TCNQ. en_US dc.format.extent 132784 bytes dc.format.mimetype image/jpeg dc.language.iso English en_US dc.publisher Ohio State University en_US dc.title METALLIC REFLECTION IN MOLECULAR CRYSTALS: THEORY OF THE DAMPING en_US dc.type article en_US
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