Provided is a compound including a
metal complex having a
metal M with a
coordination number of four with four coordinating atoms, Z1, Z2, Z3, and Z4, coordinated to the
metal M. In the compound, each of Z1, Z2, Z3, and Z4 is independently selected from O, S, Se, N, P, C, Si, or B; at least one of Z1, Z2, Z3, or Z4 is S* or Se*, where S* and Se* represent S or Se, respectively, that form a dative bond with M; and the metal M is selected from Pt, Pd, Cu, Ag, Au, or Zn, Formulations, OLEDs, and
consumer products containing the compound are also provided.