Acta Phys. -Chim. Sin. ›› 2010, Vol. 26 ›› Issue (01): 125-130.doi: 10.3866/PKU.WHXB20091219

• QUANTUM CHEMISTRY AND COMPUTATION CHEMISTRY • Previous Articles     Next Articles

Optical Characteristics of Lignin with a Quinoid Structure

CHEN Xiao-Hua, FAN Yong-Ming, CAO Chun-Yu, HU Hong-Zhi   

  1. College of Material Science and Technology, Beijing Forestry University, Beijing 100083, P. R. China; China National Pulp and Paper Research Institute, Beijing 100020, P. R. China; School of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
  • Received:2009-06-10 Revised:2009-09-21 Published:2009-12-29
  • Contact: FAN Yong-Ming E-mail:fanym@bjfu.edu.cn

Abstract:

To explore the relationship between the structures and color of a quinoid lignin, quantum chemical calculations on fivemodel lignin compounds: 2-methoxy-1,4-benzoquinone (I), 1,2-benzoquinone (II), 4-acrol-2-methoxy-2,5-cyclohexadienone (p-quinone methide) (III), 5-methoxy-1,4-benzoquinone-2-oxygen anion (IV), 5-methyl-1,4-benzoquinone-2-oxygen anion (V) were performed using density functional theory at the B3LYP/6-311++G(2d,p) level. Optimized structures were obtained using ethanol as a solvent. Electronic spectra were produced using time dependent density functional theory (TD-DFT) at the same level. Results indicated that the maximumabsorption band in the visible region of the five model compounds was caused by a π→π* transition. The location of the maximum absorption band increased according to: III

Key words: Density functional theory, Quinoid lignin, Time dependent density functional theory, Optical characteristics, Electronic spectrum

MSC2000: 

  • O641