LAPW frozen-phonon calculation, shell model lattice dynamics and specific-heat measurement of SnO
نویسنده
چکیده
An ab-initio Linear Augmented Plane-Wave (LAPW) calculation of the zonecentered phonon frequencies of SnO has been performed. Eg symmetry has been ascribed to the mode observed at 113 cm in Raman measurements, discarding a previous B1g assignement. The other phonon modes measured by Raman spectroscopy are also well reproduced. A new shell-model has also been developed, that gives good agreement of the zone-centered frequencies compared to the measured data and the LAPW results. Specific heat measurements have been performed between 5 K and 110 K. Computation of the specific heat and Present address: International Centre for Theoretical Physics, Strada Costiera 11, 34014, Trieste, Italy. Present address: Goldaracena 740, 2820 Gualeguaychu (Entre Rios), Argentina
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