Fig. 4.
Mass difference networks, presenting the chemical complexity/reactivity of the CHOMg space and its connection to CHO compositions. (A–E) Five subnetworks, each representing one distinct degree of unsaturation, as well as a gradual increase in the number of oxygen in CHOMg molecules, are shown for NWA 7325 soluble organic matter. The variance in unsaturation is expressed via DBE values. CHOMg nodes are pink and CHO nodes are blue. The nodal diameter is proportional to the natural logarithm of each mass peak’s intensity. Three types of edges are defined, the mass differences of CH2 and O illustrate the systematic connection within the CHO or CHOMg chemical space, and Δm/z(Mg(OH)2) addresses reaction pairs that connect CHO and CHOMg compositions. (F) Proposed alternative organomagnesium complex formation with unsaturated β-hydroxy ketones as chelate ligands.