Relaxation Dynamics of Electronically Excited Nanoscale Metal−Carbon Complexes:  Vanadium−Carbon Clusters

First measurements of the relaxation dynamics of electronically excited states in nanoscale transition metal−carbon species are reported. In this communication, time-resolved measurements, made with the femtosecond laser pump−probe technique by employing 50 fs pulses at 620 and 400 nm, reveal the excited-state dynamics in vanadium−carbon clusters including the vanadium Met-Car, V8C12. Size dependent trends are observed in the pump−probe transients, which suggest a more extensive free electron character in the larger clusters as compared to the smaller species.