The full set of piezoelectric stress coefficients and the spontaneous polarization of ferroelectric Im2m sodium nitrite were calculated by first-principles quantum-mechanical methods. The Berry phase approach, implemented in the periodic LCAO computational scheme, was employed with an all-electron basis set and the Hartree-Fock Hamiltonian. Suitable deformations are applied to crystal structure, and derivatives of the Berry phases are computed numerically with respect to the strain parameters, so as to obtain the e ik =(P i / k ) E quantities. The piezoelectric constants obtained were e 21 =-0.094, e 22 =0.168, e 23 =-0.092, e 34 =0.123, and e 16 =-0.127 Cm -2 . A spontaneous polarization value P s =0.169 Cm -2 was calculated for the Hartree-Fock least-energy crystal structure.
Noel, Y., Catti, M., Dovesi, R. (2004). Ab initio calculation of piezoelectric and ferroelectric properties of NaNO2. FERROELECTRICS, 300(1), 139-145 [10.1080/00150190490443839].
Ab initio calculation of piezoelectric and ferroelectric properties of NaNO2
CATTI, MICHELE;
2004
Abstract
The full set of piezoelectric stress coefficients and the spontaneous polarization of ferroelectric Im2m sodium nitrite were calculated by first-principles quantum-mechanical methods. The Berry phase approach, implemented in the periodic LCAO computational scheme, was employed with an all-electron basis set and the Hartree-Fock Hamiltonian. Suitable deformations are applied to crystal structure, and derivatives of the Berry phases are computed numerically with respect to the strain parameters, so as to obtain the e ik =(P i / k ) E quantities. The piezoelectric constants obtained were e 21 =-0.094, e 22 =0.168, e 23 =-0.092, e 34 =0.123, and e 16 =-0.127 Cm -2 . A spontaneous polarization value P s =0.169 Cm -2 was calculated for the Hartree-Fock least-energy crystal structure.
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