A polarization rule on atomic arrangements of graphite-like boron carbonitride

B and N K-edge near-edge X-ray absorption fine structure (NEXAFS) spectra of boron carbonitride (B–C–N) films prepared by ion beam deposition are interpreted by molecular orbital calculations with the core–hole effect. Model clusters with different atomic arrangements are compared in terms of photoabsorption cross section (PACS) and net charge, and they are classified into two groups, i.e., polarization and non-polarization types. PACS of π∗ peaks near the lowest unoccupied molecular orbital (LUMO) state increase at B K-edge and decrease at N K-edge for polarization type and vice versa for non-polarization type. Based on a comparison between experimental and theoretical results, we propose a rule for atomic arrangements of boron, carbon, and nitrogen atoms in graphite-like B–C–N. Finally, the relationship between the rule and structural stability is discussed.