1
|
Gallegos M, Vassilev-Galindo V, Poltavsky I, Martín Pendás Á, Tkatchenko A. Explainable chemical artificial intelligence from accurate machine learning of real-space chemical descriptors. Nat Commun 2024; 15:4345. [PMID: 38773090 DOI: 10.1038/s41467-024-48567-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Accepted: 04/24/2024] [Indexed: 05/23/2024] Open
Abstract
Machine-learned computational chemistry has led to a paradoxical situation in which molecular properties can be accurately predicted, but they are difficult to interpret. Explainable AI (XAI) tools can be used to analyze complex models, but they are highly dependent on the AI technique and the origin of the reference data. Alternatively, interpretable real-space tools can be employed directly, but they are often expensive to compute. To address this dilemma between explainability and accuracy, we developed SchNet4AIM, a SchNet-based architecture capable of dealing with local one-body (atomic) and two-body (interatomic) descriptors. The performance of SchNet4AIM is tested by predicting a wide collection of real-space quantities ranging from atomic charges and delocalization indices to pairwise interaction energies. The accuracy and speed of SchNet4AIM breaks the bottleneck that has prevented the use of real-space chemical descriptors in complex systems. We show that the group delocalization indices, arising from our physically rigorous atomistic predictions, provide reliable indicators of supramolecular binding events, thus contributing to the development of Explainable Chemical Artificial Intelligence (XCAI) models.
Collapse
Affiliation(s)
- Miguel Gallegos
- Department of Analytical and Physical Chemistry, University of Oviedo, E-33006, Oviedo, Spain
| | | | - Igor Poltavsky
- Department of Physics and Materials Science, University of Luxembourg, L-1511, Luxembourg City, Luxembourg
| | - Ángel Martín Pendás
- Department of Analytical and Physical Chemistry, University of Oviedo, E-33006, Oviedo, Spain.
| | - Alexandre Tkatchenko
- Department of Physics and Materials Science, University of Luxembourg, L-1511, Luxembourg City, Luxembourg.
| |
Collapse
|
2
|
Echeverri A, Gallegos M, Gómez T, Pendás ÁM, Cárdenas C. Calculation of the ELF in the excited state with single-determinant methods. J Chem Phys 2023; 158:2887544. [PMID: 37125705 DOI: 10.1063/5.0142918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 04/17/2023] [Indexed: 05/02/2023] Open
Abstract
Since its first definition, back in 1990, the electron localization function (ELF) has settled as one of the most commonly employed techniques to characterize the nature of the chemical bond in real space. Although most of the work using the ELF has focused on the study of ground-state chemical reactivity, a growing interest has blossomed to apply these techniques to the nearly unexplored realm of excited states and photochemistry. Since accurate excited electronic states usually require to account appropriately for electron correlation, the standard single-determinant ELF formulation cannot be blindly applied to them, and it is necessary to turn to correlated ELF descriptions based on the two-particle density matrix (2-PDM). The latter requires costly wavefunction approaches, unaffordable for most of the systems of current photochemical interest. Here, we compare the exact, 2-PDM-based ELF results with those of approximate 2-PDM reconstructions taken from reduced density matrix functional theory. Our approach is put to the test in a wide variety of representative scenarios, such as those provided by the lowest-lying excited electronic states of simple diatomic and polyatomic molecules. Altogether, our results suggest that even approximate 2-PDMs are able to accurately reproduce, on a general basis, the topological and statistical features of the ELF scalar field, paving the way toward the application of cost-effective methodologies, such as time-dependent-Hartree-Fock or time-dependent density functional theory, in the accurate description of the chemical bonding in excited states of photochemical relevance.
Collapse
Affiliation(s)
- Andrea Echeverri
- Departamento de Física, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, Chile
| | - Miguel Gallegos
- Depto. Química Física y Analítica, Universidad de Oviedo, 33006 Oviedo, Spain
| | - Tatiana Gómez
- Theoretical and Computational Chemistry Center, Institute of Applied Chemical Sciences, Faculty of Engineering, Universidad Autonoma de Chile, El Llano Subercaceaux, 2801 Santiago, Chile
| | - Ángel Martín Pendás
- Depto. Química Física y Analítica, Universidad de Oviedo, 33006 Oviedo, Spain
| | - Carlos Cárdenas
- Departamento de Física, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, Chile
- Centro para el Desarrollo de la Nanociencia y la Nanotecnología (CEDENNA), Avda. Ecuador 3493, Santiago 9170124, Chile
| |
Collapse
|
3
|
Guevara-Vela JM, Francisco E, Rocha-Rinza T, Martín Pendás Á. Interacting Quantum Atoms-A Review. Molecules 2020; 25:E4028. [PMID: 32899346 PMCID: PMC7504790 DOI: 10.3390/molecules25174028] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 08/24/2020] [Accepted: 08/26/2020] [Indexed: 12/16/2022] Open
Abstract
The aim of this review is threefold. On the one hand, we intend it to serve as a gentle introduction to the Interacting Quantum Atoms (IQA) methodology for those unfamiliar with it. Second, we expect it to act as an up-to-date reference of recent developments related to IQA. Finally, we want it to highlight a non-exhaustive, yet representative set of showcase examples about how to use IQA to shed light in different chemical problems. To accomplish this, we start by providing a brief context to justify the development of IQA as a real space alternative to other existent energy partition schemes of the non-relativistic energy of molecules. We then introduce a self-contained algebraic derivation of the methodological IQA ecosystem as well as an overview of how these formulations vary with the level of theory employed to obtain the molecular wavefunction upon which the IQA procedure relies. Finally, we review the several applications of IQA as examined by different research groups worldwide to investigate a wide variety of chemical problems.
Collapse
Affiliation(s)
- José Manuel Guevara-Vela
- Institute of Chemistry, National Autonomous University of Mexico, Circuito Exterior, Ciudad Universitaria, Delegación Coyoacán C.P., Mexico City 04510, Mexico; (J.M.G.-V.); (T.R.-R.)
| | - Evelio Francisco
- Department of Analytical and Physical Chemistry, University of Oviedo, E-33006 Oviedo, Spain;
| | - Tomás Rocha-Rinza
- Institute of Chemistry, National Autonomous University of Mexico, Circuito Exterior, Ciudad Universitaria, Delegación Coyoacán C.P., Mexico City 04510, Mexico; (J.M.G.-V.); (T.R.-R.)
| | - Ángel Martín Pendás
- Department of Analytical and Physical Chemistry, University of Oviedo, E-33006 Oviedo, Spain;
| |
Collapse
|
4
|
Casals‐Sainz JL, Guevara‐Vela JM, Francisco E, Rocha‐Rinza T, Martín Pendás Á. Efficient implementation of the interacting quantum atoms energy partition of the second‐order Møller–Plesset energy. J Comput Chem 2020; 41:1234-1241. [DOI: 10.1002/jcc.26169] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 01/30/2020] [Accepted: 01/30/2020] [Indexed: 12/19/2022]
Affiliation(s)
| | - José Manuel Guevara‐Vela
- Institute of Chemistry, National Autonomous University of Mexico, Circuito ExteriorCiudad Universitaria Mexico City Mexico
| | - Evelio Francisco
- Department of Analytical and Physical ChemistryUniversity of Oviedo Oviedo Spain
| | - Tomás Rocha‐Rinza
- Institute of Chemistry, National Autonomous University of Mexico, Circuito ExteriorCiudad Universitaria Mexico City Mexico
| | - Ángel Martín Pendás
- Department of Analytical and Physical ChemistryUniversity of Oviedo Oviedo Spain
| |
Collapse
|
5
|
Symons BCB, Williamson DJ, Brooks CM, Wilson AL, Popelier PLA. Does the Intra-Atomic Deformation Energy of Interacting Quantum Atoms Represent Steric Energy? ChemistryOpen 2019; 8:560-570. [PMID: 31065506 PMCID: PMC6496634 DOI: 10.1002/open.201800275] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 01/15/2019] [Indexed: 11/10/2022] Open
Abstract
We show that the mutual, through-space compression of atomic volume experienced by approaching topological atoms causes an exponential increase in the intra-atomic energy of those atoms, regardless of approach orientation. This insight was obtained using the modern energy partitioning method called interacting quantum atoms (IQA). This behaviour is consistent for all atoms except hydrogen, which can behave differently depending on its environment. Whilst all atoms experience charge transfer when they interact, the intra-atomic energy of the hydrogen atom is more vulnerable to these changes than larger atoms. The difference in behaviour is found to be due to hydrogen's lack of a core of electrons, which, in heavier atoms, consistently provide repulsion when compressed. As such, hydrogen atoms do not always provide steric hindrance. In accounting for hydrogen's unusual behaviour and demonstrating the exponential character of the intra-atomic energy in all other atoms, we provide evidence for IQA's intra-atomic energy as a quantitative description of steric energy.
Collapse
Affiliation(s)
- Benjamin C B Symons
- Manchester Institute of Biotechnology (MIB) 131 Princess Street Manchester M1 7DN Great Britain.,School of Chemistry University of Manchester Oxford Road Manchester M13 9PL Great Britain
| | - Dominic J Williamson
- Manchester Institute of Biotechnology (MIB) 131 Princess Street Manchester M1 7DN Great Britain.,School of Chemistry University of Manchester Oxford Road Manchester M13 9PL Great Britain
| | - Campbell M Brooks
- Manchester Institute of Biotechnology (MIB) 131 Princess Street Manchester M1 7DN Great Britain.,School of Chemistry University of Manchester Oxford Road Manchester M13 9PL Great Britain
| | - Alex L Wilson
- Manchester Institute of Biotechnology (MIB) 131 Princess Street Manchester M1 7DN Great Britain.,School of Chemistry University of Manchester Oxford Road Manchester M13 9PL Great Britain
| | - Paul L A Popelier
- Manchester Institute of Biotechnology (MIB) 131 Princess Street Manchester M1 7DN Great Britain.,School of Chemistry University of Manchester Oxford Road Manchester M13 9PL Great Britain
| |
Collapse
|
6
|
Jara-Cortés J, Landeros-Rivera B, Hernández-Trujillo J. Unveiling the role of intra and interatomic interactions in the energetics of reaction schemes: a quantum chemical topology analysis. Phys Chem Chem Phys 2018; 20:27558-27570. [PMID: 30371704 DOI: 10.1039/c8cp03775b] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
In this work we present a detailed analysis of selected reaction schemes in terms of the atomic components of the electronic energy defined by the quantum theory of atoms in molecules and the interacting quantum atoms method. The aim is to provide an interpretation tool for the energy change involved in a chemical reaction by means of the atomic and interaction contributions to the energies of the molecules involved. Ring strain in cyclic alkanes, the resonance energy of aromatic and antiaromatic molecules, local aromaticity in polycyclic aromatic hydrocarbons, intermolecular bonding in hydrogen fluoride clusters, and hydration of d-block metal dications were selected for the study. It was found that in addition to the changes in the strong C-C interactions in the carbon skeleton of the organic molecular rings, other contributions not usually considered to be important such as those between C and H atoms (either bonded or not) need to be considered in order to account for the net energy changes. The analysis unveils the role of the ionic and covalent contributions to the hydrogen bonding in HF clusters and the energetic origin and extent of cooperative effects involved. Moreover, the "double-hump" behavior observed for the hydration energy trend of [M(H2O)6]2+ complexes is explained in terms of the deformation energy of the metal cation and the increasingly covalent metal-water interactions. In addition, proper comparisons with the description provided by other methodologies are briefly discussed. The topological approach proposed in this contribution proves to be useful for the description of energy changes of apposite reaction schemes in chemically meaningful terms.
Collapse
Affiliation(s)
- Jesús Jara-Cortés
- Departamento de Física y Química Teórica, Facultad de Química, UNAM, México City, 04510, Mexico.
| | | | | |
Collapse
|
7
|
Casalz-Sainz JL, Guevara-Vela JM, Francisco E, Rocha-Rinza T, Martín Pendás Á. Where Does Electron Correlation Lie? Some Answers from a Real Space Partition. Chemphyschem 2017; 18:3553-3561. [DOI: 10.1002/cphc.201700940] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Revised: 10/04/2017] [Indexed: 11/09/2022]
Affiliation(s)
- José Luis Casalz-Sainz
- Departament of Analytical and Physical Chemistry; University of Oviedo; E-33006 Oviedo Spain
| | | | - Evelio Francisco
- Departament of Analytical and Physical Chemistry; University of Oviedo; E-33006 Oviedo Spain
| | - Tomás Rocha-Rinza
- Institute of Chemistry; National Autonomous University of Mexico, Circuito Exterior, Ciudad Universitaria, Delegación Coyoacán C.P.; 04510 Mexico City Mexico
| | - Ángel Martín Pendás
- Departament of Analytical and Physical Chemistry; University of Oviedo; E-33006 Oviedo Spain
| |
Collapse
|
8
|
Jara-Cortés J, Hernández-Trujillo J. Energetic Analysis of Conjugated Hydrocarbons Using the Interacting Quantum Atoms Method. J Comput Chem 2017; 39:1103-1111. [PMID: 29076165 DOI: 10.1002/jcc.25089] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2017] [Revised: 09/04/2017] [Accepted: 10/06/2017] [Indexed: 01/21/2023]
Abstract
A number of aromatic, antiaromatic, and nonaromatic organic molecules was analyzed in terms of the contributions to the electronic energy defined in the quantum theory of atoms in molecules and the interacting quantum atoms method. Regularities were found in the exchange and electrostatic interatomic energies showing trends that are closely related to those of the delocalization indices defined in the theory. In particular, the CC interaction energies between bonded atoms allow to rationalize the energetic stabilization associated with the bond length alternation in conjugated polyenes. This approach also provides support to Clar's sextet rules devised for aromatic systems. In addition, the H⋯H bonding found in some of the aromatic molecules studied was of an attractive nature, according to the stabilizing exchange interaction between the bonded H atoms. © 2017 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Jesús Jara-Cortés
- Departamento de Física y Química Teórica, Facultad de Química, UNAM, México City, 04510, México
| | | |
Collapse
|
9
|
The ANANKE relative energy gradient (REG) method to automate IQA analysis over configurational change. Theor Chem Acc 2017; 136:86. [PMID: 32025197 PMCID: PMC6979521 DOI: 10.1007/s00214-017-2113-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Accepted: 06/16/2017] [Indexed: 12/15/2022]
Abstract
Much chemical insight ultimately comes down to finding out which fragment of a total system behaves like the total system, in terms of an energy profile. A simple example is that of the water dimer, where this system is regarded as held together by a hydrogen bond. The hydrogen bond consists of two atoms (H···O), which energetically behave similarly to the total system (H2O)2. However, from a quantum mechanical point of view, each atom in the total system interacts with any other atom. Thus, the view that the hydrogen bond by itself governs the energetic stability of the water dimer needs rigorous justification. In this work, we propose a method that provides such a justification, in general, but only illustrated on the water dimer here. This method is based on the topological energy partitioning method called interacting quantum atoms (IQA). The method is implemented in the program ANANKE, which calculates correlations between the energy profile of the total system and those of subsystems (or fragments). ANANKE acts on the IQA energy contributions obtained for a sequence of full-system geometries controlled by a coordinate of interest (e.g. the O···H distance in the water dimer). Although applied only for the water dimer in this work, the method is general and able to explain the gauche effect, the torsional barrier in biphenyl, the arrow-pushing scheme of an enzymatic reaction (peptide hydrolysis in the HIV-1 Protease active site), and halogen-alkane nucleophilic substitution (SN2) reactions. Those applications will appear elsewhere as separate and elaborated case studies; here we focus on the details of the ANANKE method and its justification, using the water dimer as a concrete case.
Collapse
|