Optical properties of chromium(III) in trigonal KAl(MoO4)2 and monoclinic NaAl(MoO4)2 hosts

Theory of the ligand-correlated covalent effect on spin orbit coupling for Cr3+ ion doping in a variety of oxide crystals

“…B, C are the Racah parameters of the TM ion in the studied crystal [1][2][3], where B 0 % 920 cm À1 and C 0 % 3330 cm À1 [20] are the free Cr 3+ ion parameters. From Eqs.…”

“…The corresponding optical and EPR spectra have been measured by many researchers [1][2][3][4][5][6][7][8][9][10]. In theory, two theoretical methods have been employed to investigate the EPR parameters of the doped systems, of which one is the high order perturbation and the other is the complete energy matrix.…”

Local structure and EPR g factors for KAl(MoO4)2:Cr3+ and RbIn(MoO4)2:Cr3+ systems

“…When Cr 3+ ions is doped in KAl(MoO 4 ) 2 and RbIn(MoO 4 ) 2 , Cr 3+ ion will replace the host Al 3+ ion or In 3+ ion, respectively. Cr 3+ ion is surrounded by an oxygen octahedron which is distorted along one of the C 3 axis [1,3,7] and so the Cr 3+ centers in KAl(MoO 4 ) 2 and RbIn(MoO 4 ) 2 have the trigonal symmetry. The trigonal distortion can be described by means of two parameters R and θ, as plotted in Fig.…”

“…The EPR spectra of KAl(MoO 4 ) 2 :Cr 3+ and RbIn(MoO 4 ) 2 :Cr 3+ systems, which are very sensitive to the local lattice structure distortions, had been measured by Hermanowicz [3] and Zapart et al [7], respectively. The optical properties of Cr 3+ doped in trigonal KAl(MoO 4 ) 2 at temperatures ranging from 15 to 300 K have been measured by Hermanowicz et al [1]. As for isostructural family KSc(MoO 4 ) 2 and RbIn(MoO 4 ) 2 , Zapart et al [7,8] have reported two structural phase transitions by changing in the EPR spectra of the Cr 3+ ion, respectively.…”

“…KAl(MoO 4 ) 2 and RbIn(MoO 4 ) 2 are two of the double molybdates of the M I M III (MoO 4 ) 2 (M I = Li, Na, K, Rb, Cs; M III = Al, Sc, In, Fe) family, which are interesting compounds due to their optical and antiferroelectric properties, ferroelastic phase transitions [1][2][3][4][5][6][7][8][9][10]. Especially Cr 3+ ions doped in KAl(MoO 4 ) 2 and RbIn(MoO 4 ) 2 crystals, those properties may get distinctly progress.…”