Benchmark potential energy curve for collinear H3

Abstract

A benchmark-quality potential energy curve is reported for the H3 system in collinear nuclear configurations. The electronic Schrödinger equation is solved using explicitly correlated Gaussian (ECG) basis functions using an optimized fragment initialization technique that significantly reduces the computational cost. As a result, the computed energies improve upon recent orbital-based and ECG computations. Starting from a well-converged basis set, a potential energy curve with an estimated sub-parts-per-billion relative precision is generated for a series of nuclear configurations using an efficient ECG rescaling approach.