Cavity size (Technical)

So I've just finished some calculations that took up a fair amount of computing time of Raijjin. But which came to basically nothing as I just proved my hypothesis wrong. This isn't totally a bad thing as I can rule it out as a possibility. But I can't help but wonder whether someone else has had the same idea tested it realised it didn't work and therefore abandoned it, and I never heard about it as there was nothing to publish. So I ended up wasting my time by checking it. I guess this is a similar problem to what they have in Medicine and Psychology where negative trial results just sit in the bottom drawer and never get published.

It's a little different I guess as there's no way I could write up and publish every idea I had that came to nothing, it would make reading journals a nightmare sorting through all the things people had tried. I guess we could do with some kind of online wiki article where we all describe things we tried that didn't work to solve a problem so others know not to try it as well.

I might as well describe the idea. It was that as two ions come together their electric fields will partially cancel this will mean there will be a weak ion-water electrostatic interaction. The water molecules will therefore move away from ion. This will reduce the ionic solvation energy leading to a repulsive force. So I performed Quantum Chemical geometry optimisation calculations on a sodium chloride dimer with 10 water molecules around them. But in the end the water molecules barely budged at all from where they were around the single ions. I also did MD simulations around the dimer and saw that the peak in the RDF stayed in exactly the same position around the dimer. Although it lowered a little as you'd expect due to the other ion removing some water.

On the plus side I learned the basics of performing MD. Was kind of ridiculously easy, the only difficult thing pretty much was getting the files in the right format. And as a result I got vast amounts of information. I can understand why it is so widely used so easy and satisfying. The only problem is that I barely knew what to do with all that information. It was kind of overwhelming. I had a simple hypothesis that I was testing and it was great for that. But if I was just trying to understand the problem more generally I wouldn't know where to start. I get that feeling a lot reading some simulation papers, that they just throw all this information together then kind of give hand wavy interpretations of what's going on and then write it up. And it's not really clear at the end of it what's been learnt.