Raman and Infrared Signatures of Layered Boron Nitride Polytypes: A First-Principles Study.

ABSTRACT: We present a study based on first-principles calculations of the vibrational and spectroscopic properties of four types of layered boron nitride (BN) polymorphs: e-BN (AA), h-BN (AA'), r-BN (ABC), and b-BN (AB). By using density functional perturbation theory with van der Waals corrections, we calculate phonon frequencies and Raman/infrared (IR) activities at the Γ point and extract specific spectral fingerprints for each stack. In e-BN, we observe a sharp, isolated high-frequency E' mode at 1420.9cm-1 that is active in both Raman and IR. For h-BN, the characteristic Raman E2g line occurs at 1415.5cm-1. The out-of-plane IR-active A2u branch shows a mid-frequency TO/LO pair at 673.5/806.6cm-1, which closely matches experimental results. Rhombohedral

SUBMITTER: Mishra P 

PROVIDER: S-EPMC12566195 | biostudies-literature | 2025 Oct

REPOSITORIES: biostudies-literature