High-resolution spectroscopy of Holmium Perchlorate: Establishment of wavelength standard for spectrophotometer

We have investigated the excited state dynamics of Holmium Oxide (Ho 2 O 3 ) dissolved in perchloric acid using ultrafast optical pump-probe spectroscopy by exciting the samples with laser light at 350 nm and 550 nm and detecting in the visible region. Using an ultrafast spectroscopic approach, the stability of Ho 2 O 3 solution has been examined. UV–Visible spectroscopy revealed 14 bands in the Ho 2 O 3 absorption spectrum and by using ultrafast transient absorption spectroscopy , we have probed the dynamics of the excited state and studied transient absorption lifetime in the visible range. We obtained multi-exponential dynamics of carrier relaxation for Ho 2 O 3 , with time constants spanning from 0.07 to >500 ps . The lifetime of molecules has been shown to be on the order of picoseconds (ps), proving the stability of Ho 2 O 3 solution and making it suitable for use as a wavelength standard for spectrophotometer calibration.