Fig. 1: Positron binding characteristics of beryllium oxide.
From: Neural network variational Monte Carlo for positronic chemistry
a Ground-state positronic density, projected into the molecular plane, of a positron attached to a beryllium oxide molecule over a range of interatomic distances, accumulated via MCMC sampling. Image scale has been normalized by bondlength. The scale bar in the bottom left of each panel indicates the relative size of one Bohr radius, a0. The blue (red) marker indicates the position of the beryllium (oxygen) nucleus. b Energy (of the bare molecule and positronic complex), dipole moment (of the bare molecule), and positron binding energy of beryllium oxide over a range of interatomic distances. Solid (dashed) lines in the dipole moment and positron binding energy plots indicate values accumulated for the electronic singlet (triplet) projected wavefunction. Error bars indicating standard errors in the Monte Carlo estimate of each quantity are smaller than the markers. Dot markers in the dipole moment plot indicate the corresponding values obtained by Buenker et al.29. Horizontal red lines in the dipole moment and positron binding energy plots indicate the mean-field critical value for positron binding to the molecular dipole field and the positron affinity of a lone beryllium atom68, respectively.
