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The binding energies of core electrons in d-type stoichiometric diborides of several transition metals were measured by X-ray photoelectron spectroscopy. Metal core lines in the diborides shifted either to higher or to lower binding energies compared with those appertaining to corresponding elemental states and varied with the metal. The shifts were <0.6 eV. Carbides, oxides, and oxycarbides of variable stoichiometries were the major impurities detected in the diborides. The binding energy shifts showed a progressive change as the electronegativity difference between the and the metalloid (boron, carbon, nitrogen, oxygen) increased. This indicated that the bond in boro-oxycarbides may be partially ionic.

The liquid metal transfer technique is applied to form nitride and carbide coatings on ceramic substrates.

A variety of ceramic coatings have been put on ceramic substrates by the molten metal transfer technique. In the diffusion coating process a reactant metal dissolved in a molten "transfer agent" metal reacts with a substrate to form the coating. Titanium dissolved in molten tin has been reacted with silicon carbide, aluminum nitride, and silicon nitride substrates to produce titanium carbide and titanium nitride coatings, respectively. Similarly tantalum metal has been reacted to form carbide or nitride coatings. The unreacted tin is finally removed by decantation followed by acid leaching.[