Single crystals of Nd-doped NaY(WO4)2 (Nd:NYW) were grown using the Czochralski technique. Crystal cracking and the presence of inclusions were found to be the main problems associated with the growth of crystals. Thermal expansion measurements were carried out on as-grown crystal samples that were cut perpendicular to the growth direction and had different amounts of inclusions. Differential thermal analysis was also carried out on these same samples. The amount of inclusions present in the Nd:NYW crystal was found to affect the thermal characteristics of the crystal. The role of impurity phases in the Nd:NYW lattice during growth is discussed on the basis of obtained results. The inclusions present in the crystal are found to produce excessive strain in the lattice, which ultimately results in cracking of the crystal.

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The solidification behavior in the Na2WO4–Y2(WO4)3 pseudo-binary system has been investigated to find out the composition of a starting material to grow single crystals of NaY(WO4)2 using the Czochralski technique. It is demonstrated that a starting charge rich in Y2(WO4)3 restricts the formation of impurity phases and may be useful in growing single crystals of a stoichiometric composition. Crystal growth experiments were carried out on undoped and Nd-doped NaY(WO4)2 employing the starting charges with 53 mol% of Y2(WO4)3. The x-ray diffraction data of as-grown crystals were refined using the GSAS program based on the Rietveld refinement. The effective segregation coefficients of the elements measured by the x-ray fluorescence technique revealed the stoichiometric composition of the as-grown Nd:NaY(WO4)2 crystals. The presence of elements in the grown crystals and their valance state were studied using x-ray photoelectron spectroscopy.