Photophysics of complex in aqueous solutions studied by femtosecond pump–probe spectroscopy

Ultrafast pump–probe spectroscopy (λpump = 420 nm) was applied to study the primary photochemical processes for IrCl 6 2 - complex in aqueous solutions. The excitation to LMCT 2T2u state was followed by formation of an intermediate absorption completely decaying with two characteristic times of 0.5 and 18 ps. Complete recovery of the ground state is consistent with the absence of photochemical activity of visible LMCT bands of IrCl 6 2 - . Possible interpretations of the observed two times are presented.