Infrared and Raman Studies of Long-Wavelength Optical Phonons in Hexagonal Mo<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">S</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math>
Infrared and Raman measurements of lattice vibrations in hexagonal Mo${\mathrm{S}}_{2}$ have been made over the combined range 20-4000 ${\mathrm{cm}}^{\ensuremath{-}1}$. Two inf...