To what extent is quantum mechanics needed to explain the properties of water?
Thanks in advance.
Quantum mechanics is needed to explain all of the properties of atoms and molecules that underlie the properties of water.
"Does anybody know of a direct quantum mechanical explanation for the existence of the triple point of water? Please, point me to a paper or book." This is a spot-on question to ask in an open forum. The one in the OP is much too general.
Yes, I am specifically interested in the quantum mechanics behind why water is liquid at room temperature. I am told this is an unusual property caused by polarisation within the molecules, but do you need quantum mechanics? Is there a calculation, for the boiling point and what type of physics does it use?
Hydrogen bonding is very important for understanding the collective behavior of water molecules, including the possibility for hydrogen atoms to tunnel from one water molecule to another. In that sense, the properties of water are very quantum mechanical.
That said, there exists pretty good classical models of water, used in molecular dynamics, that reproduce pretty well many aspects of water.
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