Structure, photo- and triboluminescence of the lanthanoid dibenzoylmethanates: HNEt3[Ln(dbm)4]

A series of lanthanoid coordination compounds with the general formula HNEt3[Ln(dbm)4] (Ln=La, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Yb; dbm=dibenzoylmethanate) has been prepared and characterized. In addition, single crystals with Ln=La, Nd and Sm were obtained. Single crystal X-ray diffraction studies reveal that the compounds with Ln=La and Nd crystallize in the P21/c space group, while the Sm-compound crystallizes in the Pc space group. Based on powder XRD data, the compounds with Ln=Eu-Yb can be described with a monoclinic cell. Photoluminescence studies indicate that compounds with Ln=Sm and Eu exhibit bright photoluminescence characteristic of the lanthanoid ion upon excitation in the near UV range. Furthermore, HNEt3[Sm(dbm)4] has been identified as a novel triboluminescent compound.