Copper (ii) chloride is a light brown solid, which slowly absorbs moisture to form a blue-green dihydrate. According to ligand field theory, water is a stronger field ligand than chloride. As a result, the dihydrate form should have a larger d orbital splitting than the anhydrous form. Thus, the color (complementary to the wavelength absorbed) of the dihydrate form should have a longer wavelength than the anhydrous form's. But why is the opposite observed here? If my reasoning is not correct, then please tell me the reason for the color change above. Thank you very much.