The lignin is an extremely challenging natural material with wide and interesting applications, during the last two decades, great efforts have been dedicated to the study of its optical properties. About this subject have occurred many controversial opinions because of the nature and interactions of this material with other components of the vegetal cellular wall. In this work we will explore and simulate the electronic absorption and vibrations spectrums based on the semiempirical geometrical and quantum mechanics optimizations of amorphous two and tree units softwoods lignin fragments of Coniferyl Alcohol. These fragments were previously obtained using the semiempirical methods, Modified Neglect of Diatomic Overlap MNDO and Zerner's spectroscopic version of the Intermediate Neglect of Differential Overlap in configuration interactions mode: ZINDO/S CI.
Lignin; Biopolymers; Optical properties; Semiempirical methods
