The Interaction of Water with cis and trans {Ru(bpy)2(PTA)2}2+ (PTA = 1,3,5-Triaza-7-phosphaadamantane) Studied by Neutron Scattering and Ab Initio Calculations: The Interaction of Water with cis and trans {Ru(bpy)2(PTA)2}2+ (PTA = 1,3,5-Triaza-7-phosphaadamantane) Studied by Neutron Scattering and Ab Initio Ca