Quantum Definition of Molecular Structure

Molecular structure, a key concept of chemistry, has
remained elusive
from the perspective of all-particle quantum mechanics, despite many
efforts. Viewing molecular structure as a manifestation of strong
statistical correlation between nuclear positions, we propose a practical
method based on Markov chain Monte Carlo sampling and unsupervised
machine learning. Application to the D3+ molecule unambiguously shows that
it possesses an equilateral triangular structure. These results provide
a major step forward in our understanding of the molecular structure
from fundamental quantum principles.