We report on recent results obtained for longitudinal field (T1) spin
relaxation of the muonium-substituted (''muonated'') free radicals MuC
O, MuC2F4, MuC2H3F, and MuC4H8 (t-butyl), comparing with results repor
ted earlier for MuC2H4 (and MuC2D4). Some comparison with transverse f
ield (T2) data is also given. These data are fit to a phenomenological
model based on NMR theory of spin relaxation in gases. The parameters
of these fits are presented and discussed.