Electronically neutral generic.
Mono-bond type materials are a sub-class of binary materials for the Binary Material Gadget
In the chemogenesis analysis, a binary compound is defined as a material that exhibits just one type of strong chemical bond: metallic, ionic or covalent. From this it follows that the chemical elements are special case binary materials, where the two elements are the same.
The classification of binary materials defined with respect to this generic is broad: elements and some binaries such as hydrogen peroxide, H2O2, that have O-O and O-H bonds are included. Most hydrocarbons (except methane & carbene) and most boranes are excluded.