Investigation of the hydrogen transfer tautomerization process yielded metallic hydrogen bonds in the benzoquinone-like core of the switch. Bond-path framework sets B and B-sigma, comprising a three-stranded, non-minimal 3-D bond, which included the familiar QTAIM bond-path and two additional paths defining the least and most preferred directions of electron density motion, were used with QTAIM and the stress-tensor respectively. The B and B-sigma were visualized and uncovered the destabilizing effects on the hydrogen bond of the presence of an Fe atom. The lengths of B and B-sigma quantified this effect and the dependence on the position of a fluorine substituent.