Thermodynamic and Fluorescence Emission Studies on Chemosensors Containing Anthracene Fluorophores. Crystal Structure of {[(Culcl)-Cl-1]Cl}(2)Center Dot 2H(2)O [L-1 = N-(3-Aminopropyl)-N '-3-(Anthracen-9-Ylmethyl)Aminopropylethane-1,2-Diamine]