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Optical transmission range and phase matching (PM) conditions for second harmonic generation (SHG) of Er3+:YSGG and CO2 laser in indium doped GaSe:In(0.1, 1.23, 2.32 mass%) are studied in comparison with these in pure and sulfur doped GaSe:S(0.09, 0.5, 2.2, 3 mass%) crystals. No changes in transparency curve are found in GaSe crystals up to 2.32 mass% indium content, but as small change as 0.18 degrees in PM angle for 2.79 microm Er3+:YSGG laser SHG and approximately 0.06 degrees for 9.58 microm CO2 laser emission line SHG are detected. PM properties of the crystals are evaluated as a function of temperature over the range from -165 to 230 degrees C. The value of dtheta/dT, the change in PM angle with variation of temperature, is found to be very small for GaSe:In crystals. While for SHG of Er3+:YSGG laser, dtheta/dT =22"/1 degrees C only, it is as small as -4.9"/1 degrees C for that of CO2 laser radiation. Linear variation of PM angle with temperature increasing is an indicator of absence of crystals structure transformation within temperature range from -165 to 230 degrees C. Thus, application of GaSe:In solid solutions in high average power nonlinear optical systems seems to be prospective.

New noncentrosymmetric double borate Rb3EuB6O12 was synthesized by solid state reaction method, and their crystallographic parameters were obtained by Rietveld analysis. This borate crystallizes in the trigonal space group R32 with cell parameters of a = 13.4604(2) Å, c = 30.7981(5) Å, Z = 15. Their structure features a three-dimensional framework composed of [B5O10] 5groups that are bridged by Eu-O polyhedra. The existence of B5O10 group in the structure was confirmed by vibrational spectroscopy. Rb3EuB6O12 melts incongruently at 1101 K. The second harmonic generation effect of Rb3EuB6O12 is 16 times higher than that of α-quartz standard. In the luminescence spectrum, the domination of a single prominent narrow line from hypersensitive 5 D0-7 F2 manifold of Eu 3+ ions is observed, while 5 D0-7 F1 manifold and ultranarrow 5 D0-7 F0 line are of comparable peak intensity. These features are explained by specific local symmetry of Eu ion within the crystal structure of Rb3EuB6O12..

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RbEu(MoO4)2 is synthesized by the two-step solid state reaction method. The crystal structure of RbEu(MoO4)2 is defined by Rietveld analysis in space group Pbcn with cell parameters a=5.13502(5), b=18.8581(2) and c=8.12849(7) Å, V=787.13(1) Å 3 , Z=4 (RB=0.86%). This molybdate possesses its phase transition at 817 K and melts at 1250K. The Raman spectra were measured with the excitation at =1064 and 514.5nm. The photoluminescence spectrum is evaluated under the excitation at 514.5nm. The absolute domination of hypersensitive 5 D0→ 7 F2 transition is observed. The ultranarrow 5 D0→ 7 F0 transition in RbEu(MoO4)2 is positioned at 580.2nm being 0.2nm blue shifted, with respect to that in Eu2(MoO4)3.

A powder sample of CsMnMoO3F3 oxyfluoride has been prepared by solid state synthesis. The pyrochlore-related crystal structure of CsMnMoO3F3 has been refined by the Rietveld method at T = 298 K (space group Fd-3m, a = 10.59141(4) Å, V = 1188.123(8) Å3; R B = 3.44%). The stability of the cubic phase has been obtained over the temperature range T = 110–293 K by heat capacity measurements. Magnetic properties have been measured over the range of T = 2–300 K. The electronic structure of CsMnMoO3F3 has been evaluated by X-ray photoelectron spectroscopy. Chemical bonding effects have been discussed for all metal ions using binding energy difference parameters and wide comparison with related oxides and fluorides. The competition between O2– and F– ions for metal valence electrons has been found.