Identification of overtone and combination bands of organic solvents by thermal lens spectroscopy with tunable Ti:sapphire laser excitation

摘要: Abstract The dual-beam mode-mismatched thermal lens (TL) technique in the near infrared (NIR) and visible spectral regions, as well mid-infrared (MIR) absorption conventional spectroscopy, were applied to carry out a full spectroscopic characterization of chloroform, dichloromethane, methanol, ethanol. Absorption spectra due overtones combination bands C H O bond stretching acquired wide region (870–1040 nm) using tunable Ti3+:sapphire laser, enabling determination anharmonicity constants (χ) dissociation energies. Moreover, solvents diffusivities obtained coefficients ~10−4 cm−1 or lower found some transparence windows chloroform dichloromethane. TL proved be very sensitive methodology able determine with low coefficients.