Ultrafast ligand exchange: detection of a pentacoordinate Ru(II) intermediate and product formation.
The ultrafast kinetics of ligand exchange of cis-[Ru(bpy)(2)(CH(3)CN)(2)](2+) were measured in H(2)O and CH(3)CN. The formation of the (3)MLCT excited-state and a five-coordinate intermediate are observed in both solvents within 2 ps after excitation (310 nm, fwhm approximately 300 fs). The (3)MLCT excited-state undergoes vibrational cooling (5-6 ps), then decays to regenerate the ground-state with a lifetime of approximately 50 ps. In CH(3)CN, ligand recombination takes place in 28 ps, while the formation of cis-[Ru(bpy)(2)(CH(3)CN)(H(2)O)](2+) in H(2)O takes place with tau = 77 ps.
Liu
Yao
Y
Department of Chemistry, The Ohio State University, Columbus, Ohio 43210, USA.
Turner
David B
DB
Singh
Tanya N
TN
Angeles-Boza
Alfredo M
AM
Chouai
Abdellatif
A
Dunbar
Kim R
KR
Turro
Claudia
C