Vibrational phonon spectroscopy of boron nitride polymorphs: a comparison between theory and experiment

1 Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH, U.K. 2 SuperSTEM Laboratory, STFC Daresbury Campus, Keckwick Lane, Daresbury WA4 4AD, U.K. 3 School of Applied Sciences, RMIT University, Melbourne VIC 3001, Australia 4 Nion Company, 11511 NE 118 St., Kirkland, WA 98034, U.S.A. 5 STFC Rutherford Appleton Lab., Harwell Science and Innovation Campus, Didcot OX11 0QX, U.K. 6 Department of Physics, Royal Holloway, University of London, Egham TW20 0EX, U.K.