Fluorozirconate glasses

The Judd-Ofelt parameterization accounts fairly well for the properties of Nd3+ in fluoride glasses, although the calculated radiative lifetime of the 4F3/2 level is quite systematically overestimated, as compared to the experiment. For instance, for fluorozirconate glasses, the experimental lifetime is in the 400-450 ps range, to be compared with 450-500 ps for the calculated one [36]. 

The spectroscopy of the SD0 level is also a valuable tool to investigate the point symmetry of Eu3+ ions in materials. It is well-known that the 5D0 - 7F2 transition is electric-dipole in nature, while 5D0- -7Fi shows a magnetic-dipole character. 5D0-> 7F2 is totally forbidden in presence of an inversion center and it is allowed in the opposite case. Usually, in vitreous phases, where the symmetry is low, electric dipolar transitions exhibit the strongest intensity. The fluorescence spectra displayed in Fig. 8 show that both transitions have about the same intensity indicating that Eu3+ ions are in high-symmetry sites in fluorozirconate glasses, relatively to oxide glasses. 

The 4Ii3/2 - 4Iis/2 infrared emission band of Er3+ ions in fluorozirconate glass is displayed in Fig. 11. The band maximum is located at 1.53 /an and the width at half-maximum is as broad as 60 nm, which favors the use of this transition for optical amplification in the third telecommunication window. In bulk geometry, 1.6 jtm CW-laser action is reported for a Cr, Yb, Er-codoped fluoroaluminate glass slab pumped by a krypton laser [114],... 

Further in the infrared, lasing at 2.7 /xm was obtained with Er3+ in bulk fluorozirconate glasses [115,116]. Glass samples were slabs with a few-mm thickness... 

XPS has also been applied recently in this field to copper films for the study of microbial effects [55], the behavior of UO2 in mineral water [56], corrosion-resistant amorphous alloys [57]-[59], and the hydrolysis of fluorozirconate glasses [60]. 

Dejneka M., Snitzer E., Riman R.E. Spectroscopic characterization of Eu " "-doped inorganic and alkoxide sol-gel derived fluorozirconate glass and zirconium fluoride gels. J. Non-Cryst. Solids... 

All fluoride glasses have excellent optical properties and transmit more than 50% between 0.25 pm and 7pm. While fluoroaluminate glasses do not transmit as far as fluorozirconate glasses, non-ZrF4 based on heavy metal can transmit to even longer wavelengths. As a result, fluoride glasses are candidate materials for both bulk windows and fibers for the IR. 

Raman spectra of fluorozirconate glasses and melts were recorded and related to structural changes with changing Zr/F ratios. The Raman spectrum of ZrCl4 shows that the liquid contains both monomers and (ZrCl4)n species. There was evidence from Raman spectra of ZrCLt-CsCl mixtures for the formation of Cs2ZrCl6 and CsZr2Cl9. ... 

M. Mortier, A. Monteville, G. Patriarche, Devitrification of fluorozirconate glasses from nucleation to spinodal decomposition, J. Non Cryst. Solids 284, 85-90 (2001). 

J.D. Shephard, D. Fumiss, P.A. Houston, A.B. Seddon, Fabrication of mid-infrared planar waveguides from compatible fluorozirconate glass pairs, via hot spin-casting, J. Non-Cryst. Solids, 284, 160-167 (2001). 

Y. Kawamoto, M. Teramoto, T. Hatano, M. Shojiya, Preparation and etching processing of planar thin film of Pr -doped fluorozirconate glass, J. Mater. Sci., 20, 5013 5016 (2001). 

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