We report an experimental investigation of absorption, fluorescence, a
nd nonlinear absorption in a platinum-ethynyl complex. We have observe
d strong singlet absorption at 355 nm, and a weaker triplet absorption
at 520 nm. Photoluminescence measurements show a fluorescence band at
400 nm and a phosphorescence band at 520 nm, Pump-probe nonlinear abs
orption measurements confirmed that S-0-->T-1 followed by excited trip
ler-state absorption corresponds to the dominant excitation path in th
e region between 513 and 532 nm. (C) 1998 American Institute of Physic
s. [S0021-9606(98)01313-0].