  We examine the SPCE and TIP5P water models to study heat capacity effects
associated with the hydrophobic hydration and interaction of Xenon particles.
We calculate the excess chemical potential for Xenon employing the Widom
particle insertion technique. The solvation enthalpy and excess heat capacity
is obtained from the temperature dependence of the chemical potentials and,
alternatively, directly by Ewald summation, as well as a reaction field based
method. All three different approaches provide consistent results. The reaction
field method allows a separation of the individual components to the heat
capacity of solvation into solute/solvent and solvent/solvent parts, revealing
the solvent/solvent part as the dominating contribution. A detailed spacial
analysis of the heat capacity of the water molecules around a pair of Xenon
particles at different separations reveals that the enhanced heat capacity of
the water molecules in the bisector plane between two Xenon atoms is
responsible for the maximum of the heat capacity observed at the desolvation
barrier, recently reported by Shimizu and Chan ({\em J. Am. Chem. Soc.},{\bf
123}, 2083--2084 (2001)). The about 60% enlarged heat capacity of water in the
concave part of the joint Xenon-Xenon hydration shell is the result of a
counterplay of strengthened hydrogen bonds and an enhanced breaking of hydrogen
bonds with increasing temperature. Differences between the two models
concerning the heat capacity in the Xenon-Xenon contact state are attributed to
the different water model bulk heat capacities, and to the different spacial
extension of the structure effect introduced by the hydrophobic particles.
Similarities between the different states of water in the joint Xenon-Xenon
hydration shell and the properties of stretched water are discussed.
