AbstractRaman spectra of single crystals of iodoform have been investigated over the temperature range 10–300 K and under hydrostatic pressure up to 14 kbar. The pressure‐induced shifts in vibrational frequency of many different modes have been used to calculate their respective Gruneisen parameters γ which are found to vary both with the frequency and pressure. They are much greater for the intermolecular modes than for the internal modes. The infrared absorption spectra have also been observed at different temperatures and are used together with the Raman data to obtain dν/dTfor each band. Some new infrared assignments are sugg