Theoretical calculations of pressure-induced shifts of the entire energy spectrum of ruby

Abstract

The d3 ions in trigonal crystal fields are considered. On the basis of the expansion of the electron wavefunctions under pressure. the expressions for the parameters Dg. E , C. K. K' and( as functions of the linear compression ratio x are derived, and the complete d3 energy matrix in trigonal field is constructed. Wtth the P-.y dependence, by diagonalizafion of this matrix to fit only the experimental data of the red shifts of Nby RI line under quasihydrostatic pressure. the valves of three parameters for the pressure shin ($, DI and t ) are determined. Then. the values of Dq, B, C. K. K' and at various pressures are evaluated, and the pressure shins of the entire energy s p e c " of Nby are theoretidy calculated uniformly by diago&tion of the complete d3 matrix. The contributions of changes of Dq, B, C, K, K' and < to the RI and Rz red shifts and the pressure-induced change in lhe RI-R~ splitting are obtained. The wlculated results of Ihe pressure shifts are in good agreement with all the experimental data of the R-. RIand B-line groups and U and Y bands. A discussion is given and conclusions drawn.

Leaders and laggards in the thirty-year marathon of gas-discharge lasers

“…[14]. By using these values of parameters at normal pressure in this work, we can also obtain the good results of the pressure shifts which are almost the same as those in Ref.…”

Pressure dependence of spectral positions and widths of emission lines related to 5DJ→7FJ electronic transitions in Sm2+ ions doped into SrFCl single crystal

“…[12]) and in Mn 4+ -doped gadolinium gallium garnet [13] with decrease of the interelectronic repulsion (Racah parameters B and C) and of the crystal-field parameters [14,15]. The pressureinduced line shifts for the 5 D J -7 F J electronic transitions in the system under study, SrFCl:Sm 2+ , were interpreted [16,17] in the molecular orbital approximation, taking into account the contributions from the point charge, charge penetration, exchange, overlap and covalency effects responsible for changes in the crystal-field parameters under pressure.…”

Improved Ligand-Field Theoretical Calculation of R-Line Pressure-Induced Shift of MgO:V 2+

“…The PS without EPI is calculated by a theory of PS of energy spectra (e.g., see Refs. [5] and [7] and therein cited references). According to the theory, the expressions of B, C (Racah parameters), Dq (cubic-field parameter), ζ and ζ (spin-orbit coupling parameters) as functions of χ (χ = R/R 0 , where R 0 and R are the local interionic distances around Cr 3+ at normal pressure and pressure P , respectively) are given as follows:…”