The major topic in this paper is to show how spectroscopy has been used to probe the structure of water and aqueous solutions. The unique nature of the hydrogen bond is stressed, as is the near tetrahedral nature of the bonding. It is because water is bi–bi functional that it is unique.
The word ‘anomalous’ is then introduced because water, far more that any other liquid, is seen to be anomalous by thermodynamicists. This means that their equations that describe liquids as being ‘perfect’ are way out for water although they work quite well for related liquids such as methanol.