Acceleration of Inverse Molecular Design by Using Predictive Techniques

Abstract

This study addresses one of the most important drawbacks inherently related to molecular searches in chemical compound space by greedy algorithms such as Best First Search and Genetic Algorithm, i.e., the large computational cost required to optimize one or more quantum-chemical properties. Significant speedups are obtained by initial property screening via predictive techniques starting already from very small databases. It is shown that the attainable acceleration depends heavily on the molecular properties, the predictive model, the molecular descriptor, and the current size of the database. We discuss the implementation and performance of predictive techniques in molecular searches based on a fixed molecular framework with a selection of sites to be filled with groups from a chemical fragment library. It is shown that for some properties speed-ups of a factor of 5 to even 20 can be obtained, while inverse design procedures on more complex properties still reach speed-ups of a factor of 2 without losing performance.

Application of Inverse Design Approaches to the Discovery of Nonlinear Optical Switches

“…Therefore, both hexaphyrin-based NLO switches benefit from a combination of EDGs and EWGs (push-pull effect) to increase the NLO contrast. Nevertheless, the NLO contrast of the [26]-hexaphyrins is also enhanced with only EDGs, while this substitution pattern significantly decreases the NLO contrast of [30]-hexaphyrins.…”

“…The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/molecules28217371/s1, Table S1: Global iteration structures of the BFS procedure on the maximization of the NLO contrast of the 28R 26R switch with the X_Y_R 1,4 _R 2,5 _R 3,6 pattern. The static hyper-Rayleigh scattering first hyperpolarizability values of the [28]hexaphyrins and [26]hexaphyrins are given in a.u. ; Table S2: Global iteration structures of the BFS procedure on the maximization of the NLO contrast of the 28R 30R switch with the X_Y_R 1,4 _R 2,5 _R 3,6 pattern.…”

“…The static hyper-Rayleigh scattering first hyperpolarizability values of the [28]hexaphyrins and [30]hexaphyrins are given in a.u., Table S3: Global iteration structures of the BFS procedure on the maximization of the NLO contrast of the 26R → 28R → 30R switch with the X_Y_R 1,4 _R 2,5 _R 3,6 pattern. The static hyper-Rayleigh scattering first hyperpolarizability values of the [26]hexaphyrins, [28]hexaphyrins and [30]hexaphyrins are given in a.u., Table S4: Global iteration structures of the BFS procedure on the maximization of the NLO contrast of the 26R → 28R → 30R switch with the X_Y_R 1,4 _R 2,5 _R 3,6 pattern. The static hyper-Rayleigh scattering first hyperpolarizability values of the [26]hexaphyrins, [28]hexaphyrins and [30]hexaphyrins are given in a.u., Table S5: Quartiles and interquartile range (IQR) of NLO contrasts (in a.u.)…”

“…The static hyper-Rayleigh scattering first hyperpolarizability values of the [26]hexaphyrins, [28]hexaphyrins and [30]hexaphyrins are given in a.u., Table S4: Global iteration structures of the BFS procedure on the maximization of the NLO contrast of the 26R → 28R → 30R switch with the X_Y_R 1,4 _R 2,5 _R 3,6 pattern. The static hyper-Rayleigh scattering first hyperpolarizability values of the [26]hexaphyrins, [28]hexaphyrins and [30]hexaphyrins are given in a.u., Table S5: Quartiles and interquartile range (IQR) of NLO contrasts (in a.u.) of the 26R and 30R-based molecular switches., Table S6: Collection of the dataset generated during the BFS and prestudy containing the individual first hyperpolarizabilities of the OFF-and ON-state, NLO contrast of the 26R 28R switch pattern.…”

“…Recent advances in computational inverse design approaches have started to reshape the landscape of structures with enhanced optical functionalities available to nanophotonics [23,24]. Motivated by these findings and building on our expertise in developing and applying property optimization algorithms [22,25,26], we recently extended inverse design to the prominent field of molecular switches for nonlinear optical applications. In our long-standing interest in the design of porphyrinoid-based molecular switches [27][28][29], we selected hexaphyrin macrocycles as a test bed to assess the potential of inverse design approaches to identify hexaphyrin-based switches with enhanced NLO contrasts.…”