Ultrafast pump–probe spectroscopy of IrCl62− complex in alcohol solutions

Abstract

Ultrafast pump-probe spectroscopy (λ_pump = 400 nm) was applied to study the primary photophysical processes for the IrCl₆²⁻ complex in methanol and ethanol solutions. The excitation to the LMCT 2U_u′ state was followed by formation of an intermediate absorption completely decaying with three characteristic times of 300 fs, ca. 2.5 ps, and 30 ps. The corresponding processes were interpreted as the 2U_u′*→1U_g′* electronic transition, vibrational relaxation, and internal conversion to the ground state. Complete recovery of the ground state is consistent with the absence of the photochemical activity of the IrCl₆²⁻ visible LMCT bands.