Understanding the structural properties of molecules found in nature or synthesized in the laboratory has always been the bread and butter of materials scientists. These researchers rely upon sophisticated simulation techniques that incorporate the rules of quantum mechanics, the same rules which govern the molecules themselves.
The simulation-based approach has been remarkably successful, so much so that an entire field of study called materials informatics has been dedicated to it.
But there have also been instances of failure. A notable example comes from disiloxane, a silicon (Si)-containing compound consisting of a Si-O-Si bridge with three hydrogen atoms at each end. The structure is simple enough, and yet it has been notoriously difficult to estimate just how much energy is needed to bend the Si-O-Si bridge. Experimental results have been inconsistent and theoretical calculations have yielded widely different values due to the sensitivity of the calculated properties to parameter choices and level of theory.
An international research team at Japan Advanced Institute of Science and Technology has now managed to solve this problem. The team achieved this feat by using a state-of-the-art simulation technique called “first-principles quantum Monte Carlo method” that finally overcame the difficulties other standard techniques could not surmount.
Their study has been published in Physical Chemistry Chemical Physics.