Volume 49 (2006)

JAHN - TELLER EFFECT IN FIRST EXCITED STATE OF Mn⁴⁺ DOPED IN Cs₂SiF₆ CRYSTAL
Pages 1-4
A. Reisz, B. Enache, C.N.Avram

Abstract
In this paper, we study the fine structure of ⁴T_2g energy level of Mn⁴⁺ ions doped in Cs₂SiF₆ crystal, the energy splitting of the zero-phonon line of ⁴T_2g - ⁴A_2g emission band and vibronic coupling of the d³ electrons with local mode of crystal lattice. The Mn⁴⁺ substitutes the Si ion in Cs₂SiF₆ and occupies an
octahedral site surrounded by six fluorine ions in high strengths crystal field. In order to obtain the energy of the spin-orbit components Γ₆, Γ₇, Γ₈^a,Γ₈^b of ⁴T_2g state of Mn⁴⁺ we have diagonalzed the Eisenstein matrices using the parameters Dq, B, C, ξ of Mn⁴⁺ ions in O_h crystal field of host matrix. The dynamical Jahn-Teller effect in ⁴T_2g state quenches the total splitting of ⁴T_2g state by Ham effect as proven by experimental data. From the reduction of the zero- phonon line split up to values according with experimental data we have calculated the Ham reduction factor and calculated the Jahn-Teller stabilization energy.