Using In Silico Tools To Map the Structural Landscape of Nitroxyl (HNO Donor) Compounds

In the crystal engineering community, the synthesis of targeted solid-state structures with desired properties is often led through an understanding and control of intermolecular interactions in the crystal. Are there easy ways of predicting how molecules will aggregate in the solid state? To address this question, hydrogen-bond energies (electrostatics) and hydrogen-bond propensity (informatics) methods were assessed for their ability to forecast which hydrogen bonds are most likely to appear in an organic crystalline solid. A set of nine molecules also demonstrated how small chemical modifications to the chemical backbone of HNO molecules disrupted either the primary hydrogen bond synthons or the spatial connectivity in the three-dimensional lattice, thereby leading to nine unique crystal packing features. Hence, none of the structures are isostructural.