This document presents a USP Field Theory interpretation of water freezing as a donor–acceptor boundary-locking transition. Water’s bent polar geometry is treated as a four-direction boundary system: two hydrogen donor corridors and two oxygen/lone-pair acceptor corridors. Liquid water is interpreted as a high-variance regime where molecules rapidly reorient, hydrogen bonds form and break, and donor–acceptor compatibility is sampled but not persistently locked. During cooling, angular variance and effective Delta-f mismatch variance decrease, hydrogen-bond lifetime increases, and the network approaches a persistent four-neighbor tetrahedral lock. In this framework, ice Ih emerges as a low-variance donor–acceptor corridor network, while its basal-plane growth produces familiar hexagonal ice and snowflake symmetry. The document clarifies that the molecule itself does not reverse donor or acceptor character. What changes is the surrounding coordination network: liquid water samples denser, more variable local packings, while freezing selects a more open tetrahedral network. This explains, in USP language, why ice is less dense than liquid water and why sixfold symmetry appears at the lattice/growth scale. Non-replacement statement: This work does not replace quantum chemistry, hydrogen-bond theory, molecular dynamics, thermodynamics, crystallography, or standard spectroscopy. It provides a geometry-first interpretive layer linking molecular polarity, hydrogen-bond dynamics, cooling, tetrahedral ice coordination, and macroscopic hexagonal symmetry. The document includes operational metrics, spectroscopic observables, supercooled-water predictions, decision rules, and a public-safe summary.
Sadegh Sepehri (Thu,) studied this question.