Vibrational Modes in LiBC: Theory Compared with Experiment

Abstract

The search for other superconductors in the MgB2 class currently is focussed on Li{1-x}BC, which when hole-doped (concentration x) should be a metal with the potential to be a better superconductor than MgB2. Here we present the calculated phonon spectrum of the parent semiconductor LiBC. The calculated Raman-active modes are in excellent agreement with a recent observation, and comparison of calculated IR-active modes with a recent report provides a prediction of the LO--TO splitting for these four modes, which is small for the B-C bond stretching mode at ~1200 cm^{-1}, but large for clearly resolved modes at 540 cm^{-1} and 620 cm^{-1}.

4 pages, two embedded figures. Physica B (in press)

References in corpus (10)

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Cited by in corpus (7)

• Born Effective Charges and Infrared Response of LiBC
• On Heavy Carbon Doping of MgB${}_2$
• Materials and mechanisms of hole superconductivity
• Electronic and optical properties of LiBC
• Vibrational properties of hexagonal LiBC: Infrared and Raman spectroscopy
• Thermodynamic stability of Li-B-C compounds from first principles
• Electronic Structures and Phonon Spectra in Boronitride Superconductors LaMBN (M= Ni, Pt)