Accurate anharmonic frequencies are provided for molecules of current research, i.e., diazirines, diazomethane, the corresponding fluorinated and deuterated compounds, their dioxygen analogs, and others. Vibrational-state energies were obtained from state-specific vibrational multiconfiguration self-consistent field theory. (VMCSCF) based on multilevel potential energy surfaces (PES) generated from explicitly correlated coupled duster, CCSD(T)-F12a, and double-hybrid density functional calculations, B2PLYP. To accelerate the vibrational structure calculations, a configuration selection scheme as well as a polynomial representation of the PE,S have been exploited. Because experimental data, are scarce for these systems, many calculated frequencies of this study are predictions and may guide experiments to come.