Intermolecular interaction of carbon disulfide under pressure (high pressure and effective negative solvation pressure)

Raman spectra of liquid carbon disulfide (CS 2 ) were measured under high pressures and in dilution with ethanol and with heptane. The pressure and concentration dependences of the molecular vibration modes ν 1 and 2 ν 2 of CS 2 are discussed. The intermolecular distance changes simultaneously with concentration and pressure. In addition, dilution also varies the environment around the CS 2 molecule. The derivative of the intermolecular interaction energy is obtained from the frequency shift from the gas phase to the liquid phase of the ν 1 and 2 ν 2 vibrations. The results show that dilution effectively acts as negative pressures, where the intermolecular distance between CS 2 molecules increases in the mixtures with ethanol and heptane. These effective pressures and pressures give the change in the intramolecular double bond between carbon and sulfur atoms. But, these give a different effect for the damping of vibrations. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)