Latent Heat and Raman Spectrum Change on Phase Transition of Water Including Calcium Chloride

Abstract

This study investigates how Raman O-H stretching signatures may be able to track latent-heat-related energetics during water's phase transitions. Prior work on latent heat and Raman analysis of phase change is reviewed to establish theoretical approach. Building on a framework that links O-H frequency shifts to hydrogen-bond strength, we relate entropy/enthalpy variations to temperature-dependent changes in peak position and integrated intensity. Experiments on pure water and impurity-doped samples, specifically CaCl${}_2$, were performed under controlled temperatures, and spectra were deconvoluted and integrated over defined bands. The Raman metrics exhibit reproducible temperature dependence that captures the transition window, while CaCl${}_2$ induces systematic shifts and measurable modifications in the apparent latent-heat signature. These results highlight Raman spectroscopy as a quantitative probe of thermodynamic evolution and impurity effects in water and related systems.

arXiv comment9 pages, 9 figures