Wow. I've seldom seen so many errors in so small a post, so we need to set some basic physics facts straight.

First, your molecules don't "release heat/energy" by breaking down. On the contrary, they consume energy for breaking. Otherwise they'd break down immediately without any ultraviolet rays.

Second, energy is not the same as heat. In fact most of thermodynamics deals with the difference between energy and heat.

Third, ultraviolet rays are not "created because of thermodynamics", they are created by electron transitions which are described by quantum mechanics. There's no thermodynamics involved.

Forth, thermodynamics is a statistical science. It does not tell you anything about the synthesis or breakdown of single molecules. Molecule behavior and chemical reactions are governed by electrodynamics and quantum mechanics. Thermodynamics however describes the statistical behavior of particle ensembles, normally in the magnitude of 10^23 particles (Avogadro constant) or above.

Fifth, "oxygen in water" is produced by plants and algae. And at the time of abiogenesis obviously there weren't any plants and algae and thus no oxygen in the atmosphere or in water.

And sixth, as you are now permanently mentioning thermodynamics, I think it's time for your announced thermodynamics argument or lesson. Because I fail to see at the moment what thermodynamics has to do with our discussion at all.