Samar Jana

Characteristics of the energy bands and the spectroscopic parameters of Pr3+ ions in PrCl3 mixed methanol, iso-propanol and butanol solutions

An investigation on the absorption spectra of the praseodymium chloride (PrCl(3)) in methanol, iso-propanol and butanol is carried out between 190 nm and 1100 nm. We have observed and assigned six energy bands of the 4f(2) electronic configuration of the Pr(3+) ion in the visible to near-infra-red and one due to 4f5d configuration in the ultraviolet region. The 4f5d band has been detected properly for low concentration of PrCl(3). We have also constructed a free-ion Hamiltonian and calculated the energy levels of the 4f(2) configuration theoretically. Hence, the best fit free-ion parameters are deduced.

Measurements of magnetic susceptibilities and anisotropy of erbium pyrogermanate (Er2Ge2O7) crystal

Abstract Experimental results of magnetic susceptibilities (K∥,K⊥) and the anisotropy K∥ − K⊥ = ΔK of a single crystal of erbium pyrogermanate between 300 K and 21 K are reported here for the first time. At 300 K, ΔK is 8251 × 10−6 emu/mole, being 24% of bulk susceptibility K and increased by 75 times at 21 K. Crystal field (CF) analysis of the results was made considering D5h site symmetry. The experimental data were best fitted with CF parameters B20 = − 1110, B40 = 3000, B60 = − 1100 and B65 = 600 (all in cm−1). The spectral lines for 4 F 3 2 − 9 2 , 2 H 9 2 , 11 2 etc. transitions for ErPG were also explained well by these parameters. The g values for the Kramers ground state were calculated and found to be g∥ = 10.58, g⊥ = 3.82; the saturation magnetization Msat along and perpendicular to D5h axis were 686 and 248 emu/cc respectively. The paramagnetic Schottky specific heat vs T curve showed a maximum at 110 K.

Absorption spectroscopy of Eu3+ ions in CsCdCl3 crystal: an evidence of nonequivalent sites

Abstract The polarized optical absorption study of Eu 3+ ions in a CsCdCl 3 crystal reveals an interesting behaviour in their electronic energy levels. In the crystal the trivalent Eu 3+ ions replace the divalent Cd 2+ ions; in order to maintain the charge neutrality the Eu 3+ ions associate in pairs accompanying one vacancy. Our observation shows that the Eu 3+ ions form two types of pair: (i) Eu 3+ –vacancy–Eu 3+ ; and (ii) vacancy–Eu 3+ –Eu 3+ , and the Eu 3+ ions feel two different trigonal ( C 3v ) electrostatic crystal fields in these two types of pair. As a result they produce pair-type of absorption spectra for each energy level. The occurrence of two distinct lines corresponding to 7 F 0 → 5 D 0 transition elucidates the presence of two nonequivalent sites in the crystal.

Zeeman spectroscopy of Nd3+ ions in CsCdCl3 crystal

A transverse Zeeman study of the high-concentration Nd3+-doped CsCdCl3 crystal at 25 K in an external magnetic field of 7.8 T applied both parallel and perpendicular to the c axis, is presented here. Observed splittings of the transitions 4I9/2→4G5/2 and 4I9/2→2G7/2 of the 4f3 electronic configuration of Nd3+ ions are investigated in detail. From the observed splittings for B‖c, the parallel splitting factors s‖ are determined for the levels in these multiplets. But for B⊥c no resolvable splitting is found at any level in these two multiplets.