Fig. 3: The structure-property relationships of K5Ba2(B10O17)2(BO2).
From: Expanding the chemistry of borates with functional [BO2]− anions
a–c The structure-property relationships of K5Ba2(B10O17)2(BO2). Frontier orbitals (isosurface) and partial density of states of O in K5Ba2(B10O17)2(BO2). d Calculated HOMO–LUMO gap (Eg) and polarizability anisotropy of B(11)O2, B(1)O3, and B(3)O4 units in K5Ba2(B10O17)2(BO2). The polarizability anisotropy of BO2 units is even larger than those of BO3 and BO4 units. Thus, larger birefringence, as determined by polarizability anisotropy, can be expected in BO2-containing borates. e, f Theoretical structural model of K(BO2) with solely BO2 units derived from K5Ba2(B10O17)2(BO2). g The phonon dispersion of K(BO2). There are no soft modes at any wave vectors and none of the imaginary phonon modes are observed, demonstrating that K(BO2) is dynamically stable.
