One of my friends is physically attracted towards me. He is a man of principle & has high moral values. But cannot resist the urge of hugging me or being physical with me. But he says this is not a love but just a chemistry that we both share. What is this chemistry & if there is even a little bit of love/ affection involved in it how I would convince him that he loves me.

He is clear in his mind for feelings that he has for you, but probably you are unable to accept the fact that he is just physically attracted and no emotional involvement is there. If you are comfortable with this equation then you may continue or else discuss your emotional need openly with him.