Fig. 4: Dissociation curves and density transformation for linear molecules.
From: Completing density functional theory by machine learning hidden messages from molecules
Dissociation curves of a C2H2 and b N2 are calculated using the NN-based meta-GGA and other existing meta-GGA functionals. For C2H2, the two C–H bonds are dissociated symmetrically along the original bond direction. The horizontal axis shows the bond length, and the vertical axis shows energy relative to the atomized limit (Eatomized). The magenta dashed lines and “x” marks show the bond lengths and the atomization energies from experiments32. The “o" marks show the peaks of each curve. Density transformations of c C2H2 and d N2 due to binding are calculated using the CCSD method and DFT with the NN-based meta-GGA functional. The densities of the single CH radical and N atom are plotted as blue lines, and the densities of the bonded molecules are plotted as red lines. They are plotted along the 1D coordinate x penetrating the centers of those molecules.
