What can theory say about the existence and properties of anomalous water?

Abstract

An important, but little practiced, function of theory is to provide working models that unify and summarize experimental findings during the time when basic understanding of a phenomenon is actually evolving. Such a model for anomalous water has been previously proposed by us [ Science, 167, 1443 (1970)]. This model attempted to explain the phenomenon as (H 2O) n with a new type of chemical bonding, and its ability to correlate existing data is brought up to date in this paper. However, three new results invalidate our original model: (a) high-accuracy ab initio calculations showing that symmetric hydrogen bonds are 5 kcal/H-bond higher in energy than the usual asymmetric hydrogen bonds, (b) calculations showing absence of a strong, long-range wall effect, (c) a molecular weight measurement by Derjaguin et al. indicating an average value of 180. Because our original model did so well in consistently correlating such a wide variety of experimental data, our present disproof of this model leads us to conclude that polywater does not exist. Experimental reports suggesting a collection of organic and/or inorganic impurities as the origin of the properties attributed to anomalous water are critically analyzed and found inconclusive. Three other related hypotheses are examined theoretically and also found inadequate. Another working model based on trace amounts of silicates plus inorganic and/or organic anions is proposed on theoretical grounds. A list of key experiments is offered to help elucidate the fundamental nature of the anomalous material and to test this model.