Chemical Analysis and Orientation Evaluation of Benzimidazobenzophenanthroline (BBL) Polymer Films by Using Soft X-ray Absorption Spectroscopy and the First-Principles Calculations (2); Band Calculation of the BBL Polymer

Abstract

To characterize benzimidazobenzophenanthroline (BBL) polymer films which are materials for graphite ultrathin films, X-ray absorption near edge structure (XANES) spectra in the C K, N K and O K regions of the BBL polymer films were analyzed by using the first-principles calculations. In the calculations, BBL polymer unit takes an orthorhombic structure. The measured XANES profiles were reproduced by the calculated XANES, which suggested the intermolecular effects between the BBL layers. However, peak intensity of the measured characteristic peaks in C K- and O K-XANES cannot be reproduced by the calculations. It is therefore confirmed that BBL polymers may take more complicated layer structure.