It exhibits superconductivity at relatively high temperature of 8.4 K and, similar to LaB6, is an electron cathode.

It has a large lattice constant (2.344 nm), high thermal and mechanical stability, and therefore is used as a diffraction grating for low-energy synchrotron radiation (1–2 keV).

[6] High-quality YB4 crystals of few centimeters in size can be grown by the multiple-pass floating zone technique.

[7] YB6 is a black odorless powder having density of 3.67 g/cm3; it has the same cubic crystalline structure as other hexaborides (CaB6, LaB6, etc., see infobox).

[2] High-quality YB6 crystals of few centimeters in size can be grown by the multiple-pass floating zone technique.

[7][8] YB6 is a superconductor with the relatively high transition temperature (onset) of 8.4 K.[8][9] YB12 crystals have a cubic structure with density of 3.44 g/cm3, Pearson symbol cF52, space group Fm3m (No.

[12][13] YB25 crystals can be grown by heating a compressed pellet of yttria (Y2O3) and boron powder to ~1700 °C.

This makes it difficult to grow a single crystal of YB25 by the melt growth method.

Two independent structure analyses [15][16] came to the same conclusion that the total number of boron atoms in the unit cell is 1584.

A schematic drawing under it indicates relative orientations of the supericosahedra, and the B80 clusters are depicted by light green and dark green spheres, respectively; at the top surface of the unit cell, the relative orientations of the supericosahedra are indicated by arrows.

[19] High-quality YB66 crystals of few centimeters in size can be grown by the multiple-pass floating zone technique and be used as X-ray monochromators.

[18] This property, together with high thermal and mechanical stability resulted in application of YB66 as dispersive elements of X-ray monochromators for low energy radiation (1–2 keV).