Preparation, characterisation, and europium-151 Mössbauer spectra of some carbides, nitrides, nitride-carbides, cyanides, and thiocyanates of europium

Abstract

The reaction of europium metal with HCN and (CN)₂ at elevated temperatures has been shown to yield Eu₂C₃, EuC₂, and compounds of the type EuN_xC_y. X-Ray parameters for these phases are reported and they are shown by ¹⁵¹Eu Mössbauer spectroscopy to be band systems. EuN is shown to be ionic and to contain Eu³⁺ ions. The reactions in liquid NH₃ of europium with HCN, C₂H₂, and NH₄SCN have been shown to produce europium(II) and europium(III) cyanide, europium(III) acetylide, and europium(III) thiocyanate respectively. The width of the ¹⁵¹Eu Mössbauer resonance is discussed in relation to possible bonding situations and the relationship between chemical isomer shift and bond ionicity is considered.