Piroto Duarte, J. ; Vilao, R.C. ; Alberto, H.V. ; Gil, J.M. ; Gil, F.P.S.C. ; Weidinger, A. ; Ayres De Campos, N. ; Fostiropoulos, K.: Muoniated radical states in the organic semiconductor phthalocyanine. Physical Review B 73 (2006), p. 075209/1-6
10.1103/PhysRevB.73.075209
Abstract:
Phthalocyanine samples of ZnPc, H2Pc and CuPc were investigated by the muon spin rotation (μSR) technique. In ZnPc and H2Pc, three muoniated radical states of paramagnetic origin were identified, two of which having hyperfine interactions in the range 110-150 MHz and correspondign to muonium addition at the outer benzene rings. The third state presents a smaller hyperfine interaction (about 25 MHz), and is tentatively assigned to addition at bridging nitrogen atoms. CuPc has an unpaired electron from the Cu atom, which originates a diamagnetic-like signal upon muonium addition. The signal exhibits two components with very different relaxation rates, corresponding to two different spatial couplings of the Cu electron with the muonium¿s electron.