Photoluminescence of Germanium(II), Tin(II) and Lead(II) Chloride Complexes in Solution

The absorption and emission spectra of GeC13-, SnC13-, PbC13-, and PbC142- in acetonitrile were recorded. In addition, emission quantum yields and lifetimes were determined. The emitting excited states are of the metalcentered sp type and originate from the 3P state of the free s2 ions. It is suggested that the complex ions which have trigonal-pyramidal C3” (MC13-) and seesaw C2, (PbC1d2-) structures in the ground state rearrange toward trigonalplanar D3h and tetrahedral Td geometries, respectively, in their sp excited states