Muon radical states in some electron donor and acceptor molecules

Muon radical states were studied in the electron donor molecules TTF and BEDT-TTF and in the electron acceptor molecule TCNQ. Muonium addition to double bond carbon sites results in hyperfine coupling contants ranging from 350 MHz in TTF down to 80 MHz for TCNQ. In TTF and BEDT-TTF additional radical states with extremely low hyperfine coupling constants in the 5 MHz region are observed; these are assigned to muon addition at sulphur sites accompanied by C — S bond cleavage. Copyright © 2000 John Wiley & Sons, Ltd.