Dielectric relaxation in water in the neighborhood of 4°C

The complex permittivity of water has been measured at seven temperatures between 3 and 5°C over a frequency range of 0.4–4 GHz. The data are analyzed first in terms of a small but significant distribution of relaxation times of magnitude larger than that observed previously and then as two separate Debye process having relaxation times separated by a factor of ∼2. It is shown that one possible interpretation of these observations is that a bond breaking process takes place in which the rate of formation of one bonded molecules from two bonded molecules depends upon whether the latter are bonded symmetrically or unsymmetrically. The value of the high frequency permittivity (ε∞) calculated from this model is shown to agree well with experiment. There is no evidence of any abrupt changes (``kinks'') greater than random experimental error in the temperature variation of the dielectric parameters of water between 3–5°C.