Ab Initio Prediction of the Stable Polymorphs of 4-amino-3,5-dinitrobenzamide (DOPLOL)

Abstract

An ab initio crystal structure prediction study, starting from gas phase optimization of the molecule at the B3LYP level, with crystal structure generation using a global search algorithm, and lattice energy minimization within an exp-6 repulsion -dispersion potential, was carried out to generate the stable lattice energy minima of 4-amino-3,5-dinitrobenzamide (DOPLOL). The hypothetical structures with favorable packing and cell volume generated from the global search were reminimizedwith a distributed multipole model of the charge density of the molecule. The possible stable polymorphs of DOPLOL from the lower energy region of the generated energy landscape plot were analyzed. The hypothetical lattice energy minimized DOPLOL structures with packing motifs and intermolecular short contacts similar to known experimental DOPLOL crystal structures were analyzed in detail to authenticate the energy landscape. Thermodynamic stability of theoretically predicted structures of DOPLOL were verified from the second derivative mechanical properties evaluated from the hessian matrix and simulated PXRD patterns were generated.

Crystal Structure, Hirshfeld Surface, Optical, Thermal, NLO, and DFT Analyses of 5‐Methyl‐1H‐Imidazole‐3‐Ium‐4‐ Carboxybutanoate crystal

“…The Hirshfeld surface is used to find out intermolecular interactions within molecular crystals. [ 24–26 ] The Hirshfeld surfaces and 2D fingerprint plots are generated using Crystal Explorer 3.1 software. [ 27 ] By determining the normalized contact distance based on the distances to the surface from inside (d i ) and outside (d e ), the intermolecular contacts can be identified concerning van der Waals radii.…”