Electronic Spectra of a Zwitterionic Molecular Crystal: Picolyltricyanoquinodimethane

Abstract

Polarized reflection spectra and the kramers-kroning transformed absoption spectra of the crystalline picolylricyanoquinodimethane (P3CNQ) are presented. Observance of an intermolecular CT transition at 12400 cm-¹, besides an intramolecular CT excitaion at 18600 cm ⁻¹, has been reported for this homo-molecular crystal. On different crystalline foaces occurrence of the same IRCT band at an energy separation of the order of thousands of wave number has been explained in the light of the excition energy shift. For both the IRCT and INCT transitions, band energies, oscillator strengths etc. are calcualated in view of the compostie molecule model. Am important emphasis is paid to the CT transition that takes place intermolecularly.

Keywords:

• Keywords
• Electronic spectra
• charge transfer band
• (Zwitterionic) molecualar crystal