Real‐time quantum chemistry

Abstract

Significant progress in the development of efficient and fast algorithms for quantum chemical calculations has been made in the past two decades. The main focus has always been the desire to be able to treat ever larger molecules or molecular assemblies-especially linear and sublinear scaling techniques are devoted to the accomplishment of this goal. However, as many chemical reactions are rather local, they usually involve only a limited number of atoms so that models of about 200 (or even less) atoms embedded in a suitable environment are sufficient to study their mechanisms. Thus, the system size does not need to be enlarged, but remains constant for reactions of this type that can be described by less than 200 atoms. The question then arises how fast one can obtain the quantum chemical results. This question is not directly answered by linear-scaling techniques. In fact, ideas such as haptic quantum chemistry (HQC) or interactive quantum chemistry require an immediate provision of quantum chemical information which demands the calculation of data in ' 'real time.' ' In this perspective, we aim at a definition of real-time quantum chemistry, explore its realm and eventually discuss applications in the field of HQC. For the latter, we elaborate whether a direct approach is possible by virtue of real-time quantum chemistry.

Interactive Chemical Reactivity Exploration

“…Haptic Quantum Chemistry [7,8], Interactive Quantum Chemistry [9,10] and Real-time Quantum Chemistry [11,12] offer new alternative approaches to study reactivity in large three-dimensional molecular systems by providing an instantaneous response of the system to the structural manipulation.…”

Mode‐tracking based stationary‐point optimization

“…Moreover, a feature of our approach is that the initial molecular distortion to be followed can be set up in a very general way to accommodate chemical insight into the system under study. Hence, interference by the operator who launched the search is a desired feature for the exploration of chemical reactions in complex systems, especially if this can be done in an interactive manner with methods based on real‐time quantum chemistry …”

“…Hence, interference by the operator who launched the search is a desired feature for the exploration of chemical reactions in complex systems, especially if this can be done in an interactive manner [38] with methods based on real-time quantum chemistry. [39] Our algorithm can be executed in an explorative fashion as we can circumvent the NEB or FSM calculation by starting from only one minimum-energy structure and by following several eigenvectors in one optimization in parallel. We will demonstrate these capabilities at the example of the isomerization reactions of formaldehyde, which has been studied as a benchmark system for automated transition-state search algorithms.…”

A GPU-accelerated immersive audio-visual framework for interaction with molecular dynamics using consumer depth sensors

“…These systems allow humans to watch simulation progress generated from molecular dynamics (MD) simulations, 2 molecular docking, 3,4 hybrid structure prediction tools, 5 course-grained models, 6 and even quantum chemistry methods. 7 'On-the-y' visualization naturally led a number of groups to investigate interactive interfaces for molecular simulation. 8 Broadly speaking, there are three levels at which interactivity has been introduced within MD simulations:…”

“…14,15 (3) Molecular substituents, where the user can pinpoint particular atoms or functional groups and manipulate them with an external force, thereby 'steering' the simulation program's internal propagation, similar to the sort of manipulations which are possible using atomic force microscopy (AFM) experiments. 16 Keyboard and mouse interfaces are utilized in such systems, 5,17 but the most popular interface has been haptic devices, 3,4,7,[18][19][20][21][22][23][24][25][26][27][28] which offer up to six degrees of freedom (compared to two for a mouse). As such, they are well suited to facilitating user interaction with 3D molecular simulations.…”