EXCITATION ENERGY TRANSFER FROM CHROMIUM IN CATION TO CHROMIUM IN ANION IN SOME CRYSTALLINE COMPOUNDS - [CRA6][CR(CN)6].XH20

Luminescence measurements indicate, in a series of double complex salts [CrA6] [Cr(CN)6].xH2O and [Cr(A-A)3] [Cr(CN)6].xH2O, where A and (A-A) are mono- or bidentate neutral ligands with oxygen or nitrogen as coordinating atoms, an excitation energy transfer from chromium in the cation (donor, D) to chromium in the anion (acceptor, A). Relative emission intensities and lifetimes of the phosphorescence 2Eg → 4A2g of the acceptor are reported. It is suggested that a doubletdoublet transfer D*(doublet) + A(quartet) → D(quartet) + A*(doublet) is operating. Possible types of mechanism are discussed. © 1969, American Chemical Society. All rights reserved.