By means of both a theory for pressure-induced shifts(PS) energy spectra and a theory for shifts of energy spectra due to electron-phonon interaction(EPIP.the pure electronic PS and the PS due to EPI of R1 line,R2 lin...By means of both a theory for pressure-induced shifts(PS) energy spectra and a theory for shifts of energy spectra due to electron-phonon interaction(EPIP.the pure electronic PS and the PS due to EPI of R1 line,R2 line,and U band of GSGG:Cr^3+ at 300 K have been calculated,respectively.The calcualted results are in good agreement with all the experimental data.Their physical origins have also been explained.It is found that the mixingdegree of t2^2(^3T1)e^4T2) and |t2^3 3E>base-wavefunctions in the wavefunctions of R1 level of GSGG:Cr^3+ at 300K is remarkable under normal pressure,and the mixing-degree rapidly decreases with increasing pressure.The change of the mixing-degree with pressure plays a key role not only for the pure electronic'PS of R1 line and R2 line but also the PS of R1 line and R2 line due to EPI.The pressure-dependent behaviors of the pure electronic 'PS of R1 line(or R2 line) and the PS of R1 line(or R2 line) due to EPI are quite different.It is the combined effect of them that gives rise to the total PS of R1 line(or R2 line).In the range of about 15 kar-45kbar,the mergence and /or order-reversal between t2^2(3T1)e^4T2 levels and t2^32T1 levels take place,which cause the fluctuation of the rate of PS for t2^2(3T1)e^4T2(or t2^32T1) with pressure,At 300K,both the temperature-dependent contribution to R1 line(Or R2 line or U band) from EPI and the temperature-independent one are important.展开更多
文摘By means of both a theory for pressure-induced shifts(PS) energy spectra and a theory for shifts of energy spectra due to electron-phonon interaction(EPIP.the pure electronic PS and the PS due to EPI of R1 line,R2 line,and U band of GSGG:Cr^3+ at 300 K have been calculated,respectively.The calcualted results are in good agreement with all the experimental data.Their physical origins have also been explained.It is found that the mixingdegree of t2^2(^3T1)e^4T2) and |t2^3 3E>base-wavefunctions in the wavefunctions of R1 level of GSGG:Cr^3+ at 300K is remarkable under normal pressure,and the mixing-degree rapidly decreases with increasing pressure.The change of the mixing-degree with pressure plays a key role not only for the pure electronic'PS of R1 line and R2 line but also the PS of R1 line and R2 line due to EPI.The pressure-dependent behaviors of the pure electronic 'PS of R1 line(or R2 line) and the PS of R1 line(or R2 line) due to EPI are quite different.It is the combined effect of them that gives rise to the total PS of R1 line(or R2 line).In the range of about 15 kar-45kbar,the mergence and /or order-reversal between t2^2(3T1)e^4T2 levels and t2^32T1 levels take place,which cause the fluctuation of the rate of PS for t2^2(3T1)e^4T2(or t2^32T1) with pressure,At 300K,both the temperature-dependent contribution to R1 line(Or R2 line or U band) from EPI and the temperature-independent one are important.
