YB4 (yttrium Tetraboride)
YB4 has tetragonal crystal structure with space group P4/mbm (No. 127), Pearson symbol tP20, a = 0.711 nm, b = 0.711 nm, c = 0.4019 nm, calculated density 4.32 g/cm3. High-quality YB4 crystals of few centimeters in size can be grown by the multiple-pass floating zone technique.
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