Effect of codoping of rare earth elements and Cr on multiferroic, optical and photocatalytic properties of BiFeO3

First-principles study on the structural, elastic, electronic, optical and thermophysical properties of NaNO3 and K-doped NaNO3

“…The spontaneous polarization is calculated using modern theory of polarization according to which the spontaneous polarization is closely related to the Berry phase of the electronic Bloch-wave functions. The sum of the electronic ( ) P elec and ionic ( ) P ion contributions can be used to calculate the total polarization 'P' for the particular crystalline geometry [47,48]. The Bloch equation of state is employed for the computation of electronic polarization contribution to 'P' from atomic translation, and the ionic polarization contribution is calculated by multiplying the ion positions of each unit cell by the nominal charge of their rigid core using an identified basis vector.…”