| abstract |
Organometallic complexes comprising a divalent lanthanide metal cation complexed with from one to three polydentate ligands which preferably contain one or more pyrazolyl groups, such as trispyrazolylborate anions, are useful in light emitting devices e.g., in electroluminescent flat panel displays. n In the complexes, several classes of which are novel, the lanthanide metal is preferably Eu since the Eu complexes have the ability to exhibit bright electroluminescence ranging from yellow to orange to blue. |