Vibrational Modes in LiBC: Theory Compared with Experiment

J. M. An; H. Rosner; S. Y. Savrasov; W. E. Pickett

doi:10.1016/s0921-4526(02)01796-9

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Vibrational Modes in LiBC: Theory Compared with Experiment

J. M. An·H. Rosner·S. Y. Savrasov·W. E. Pickett

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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}.

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J. M. An, H. Rosner, S. Y. Savrasov, W. E. Pickett. 2002-09-11. Vibrational Modes in LiBC: Theory Compared with Experiment. https://doi.org/10.1016/s0921-4526(02)01796-9

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