Temperature dependence of the thermo-optical properties of water determined by thermal lens spectrometry

Abstract

The high transparency of water makes conventional spectroscopic measurements very difficult to be performed. In this work thermal lens spectrometry is applied to determine the temperature dependence of the thermo-optical properties of distilled and de-ionized water. The experiments were performed in the temperature range between 22 and 70 °C using the mode mismatched thermal lens configuration. The results showed three anomalous regions for the thermo-optical coefficients around 39, 42, and 59 °C. These observations may contribute to a better understanding of the physical and chemical properties of water.