Bubin, SergiyStanke, MonikaAdamowicz, Ludwik2016-01-272016-01-272009Sergiy Bubin, Monika Stanke, Ludwik Adamowicz; 2009; Non-Born–Oppenheimer calculations of the BH molecule; THE JOURNAL OF CHEMICAL PHYSICShttp://nur.nu.edu.kz/handle/123456789/1057Variational calculations employing explicitly correlated Gaussian basis functions have been performed for the ground state of the boron monohydride molecule BH and for the boron atom B . Up to 2000 Gaussians were used for each system. The calculations did not assume the Born–Oppenheimer BO approximation. In the optimization of the wave function, we employed the analytical energy gradient with respect to the Gaussian exponential parameters. In addition to the total nonrelativistic energies, we computed scalar relativistic corrections mass-velocity and Darwin . With those added to the total energies, we estimated the dissociation energy of BH. The non-BO wave functions were also used to compute some expectation values involving operators dependent on the interparticle distancesenResearch Subject Categories::NATURAL SCIENCES::PhysicsHD moleculeArticle