Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

The Quantum Chemistry of Reactivity. The Quantum Chemistry of Reactivity. The Photonic Hypothesis

Eduardo Medina de la Rosa, Ramiro García

Published Dec 1, 2003• 0 citations
OpenAlex

Abstract

In this paper we introduce several ideas on the quantum chemical aspects of the reactivity as the new definition of reaction coordinate, microchemical reaction system, microchemical equilibrium, “excluding” global Hamiltonian, global wavefunction for a microchemical reaction system, and develop many of them . Also we pretend introduce the time dependent Schrodinger equation and use the programmable computational program Maple 9.5 for solving it.

Related papers

Revisiting the Schrödinger Equation in Molecular Reaction Dynamics and a New Perspective of Quantum Chemistry

Hiroyuki Nohira, Toshiyuki Nohira

The applicability of the time-dependent Schrödinger equation to molecular reaction dynamics is discussed from several perspectives. First, with reference to Schrödinger's original paper, we point out that he himself stated that what is now called the time-dependent Schrödinger equation is insufficient to solve the problems of non-conservative systems like chemical reactions. Second, the detonation velocity of some explosives has been demonstrated as a new parameter that directly illustrates the timescales of elementary chemical reactions. The calculated values of ~30 fs are in good agreement with the timescale of 10–100 fs for chemical reactions, as experimentally demonstrated by the Nobel laureate Zewail. Third, we consider the state of an electron in a box when the length of the box suddenly increases from L to 2L, which is often found in textbooks as the simplest example of the application of the time-dependent Schrödinger equation to chemical reactions, and highlight the inconsistency between this model and an actual chemical reaction. Finally, we re-iterate that only quantum steady states can be accurately described by the Schrödinger equation and that it is the most natural to connect changes between adjacent quantum steady states by the variational principle.

•Jun 30, 2025•0 citations

Real-time Quantum Chemistry

Moritz P. Haag, Markus Reiher

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 al-ways been the desire to be able to treat ever larger molecules or molecular assemblies— especially linear and sub-linear 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 two hundred (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 two hundred 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 or interactive quantum chemistry require an immediate provision of quan-tum 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 haptic quantum chemistry. For the latter we elaborate whether a direct approach is possible by virtue of real-time quantum chemistry. Submitted for publication as a perspective article in Int. J. Quantum Chem.

•Jan 1, 2012•37 citations

Quantum by Quantum: Quantum Chemistry by Quantum computation

Carlos Amador‐Bedolla, Alán Aspuru‐Guzik

Superposition and entanglement are properties of the quantum nature that suggest the construction, programming and functioning of quantum computers. Specifically, they have been imagined as a means for solving the Schrodinger equation and calculating the energy of a quantum system, i. e. doing quantum chemistry on quantum computers. It has been shown recently that this is possible in principle. We present the basic ideas of the quantum algorithm for the solution of Schrodinger´s equation and the estimation of the resources needed for a quantum computer to achieve this task.

•Sep 23, 2011•0 citations

Time evolution of a small reactive system

J. P. Badiali

We investigate the irreversible evolution of a small system in which a chemical reaction takes place.We have two main goals: the first requires to find an equation to produce a time-irreversible behavior,the second consists in introducing a simple exactly solvable model in order to understand basic facts in chemical kinetics.Our basic tool is the transition function counting the number of paths joining two points in the reactive coordinates system.An exact quantum Smoluchowski equation is derived for the reactive system in vacuum, in the presence of a solvent in equilibrium at any time with the reactive system a new Smoluchowski equation is obtained.The transition from a quantum regime to a classical one is discussed.The case of a reactive system not in equilibrium with its neighborhood is investigated in terms of path integral and via a partial differential function.Memory effects and closure assumptions are discussed.Using a simple potential model, the chemical rate constant is exactly calculated and questions such as the meaning of the activation energy or the physical content of the so-called prefactor are investigated.

arXiv:1312.4409•Condensed Matter Physics•Jan 1, 2013•1 citation

Quantum chemistry – from the first steps to linear-scaling electronic structure methods

Daniel Gräf, Viktoria Drontschenko, Alexandra Stan-Bernhardt +1 more

We first give a brief, incomplete overview over historic milestones leading to the emergence of quantum chemistry, starting from John Dalton's earliest attempts to describe the atom in the early 19th century. After the formulation of the Schrödinger equation in 1926 and the first successful description of covalent bonding using the new theory, it became soon clear that the main challenge ahead was to find efficient approximations to the Schrödinger equation, as was famously stated by Paul A. M. Dirac in 1929. Since then, many quantum-chemical approximations have been introduced, with a key problem being the exponential increase of the computational cost with the system size when approaching the exact solution of the Schrödinger equation. In the second part, we will hence focus on selected techniques to overcome the scaling problem. Finally, we close with some insights into the new and challenging field of reaction network exploration, offering a glimpse into potential future directions of quantum chemistry.

Pure and Applied Chemistry•Nov 1, 2025•2 citations

Real‐time quantum chemistry

Moritz P. Haag, Markus Reiher

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. © 2012 Wiley Periodicals, Inc.

arXiv:1208.3717•International Journal of Quantum Chemistry•Oct 12, 2012•39 citations
In this paper we introduce several ideas on the quantum chemical aspects of the reactivity as the new definition of reaction coordinate, microchemical reaction system, microchemical equilibrium, “excluding” global Hamiltonian, global wavefunction for a microchemical reaction system, and develop many of them . Also we pretend introduce the time dependent Schrodinger equation and use the programmable computational program Maple 9.5 for solving it.
The applicability of the time-dependent Schrödinger equation to molecular reaction dynamics is discussed from several perspectives. First, with reference to Schrödinger's original paper, we point out that he himself stated that what is now called the time-dependent Schrödinger equation is insufficient to solve the problems of non-conservative systems like chemical reactions. Second, the detonation velocity of some explosives has been demonstrated as a new parameter that directly illustrates the timescales of elementary chemical reactions. The calculated values of ~30 fs are in good agreement with the timescale of 10–100 fs for chemical reactions, as experimentally demonstrated by the Nobel laureate Zewail. Third, we consider the state of an electron in a box when the length of the box suddenly increases from L to 2L, which is often found in textbooks as the simplest example of the application of the time-dependent Schrödinger equation to chemical reactions, and highlight the inconsistency between this model and an actual chemical reaction. Finally, we re-iterate that only quantum steady states can be accurately described by the Schrödinger equation and that it is the most natural to connect changes between adjacent quantum steady states by the variational principle.
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 al-ways been the desire to be able to treat ever larger molecules or molecular assemblies— especially linear and sub-linear 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 two hundred (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 two hundred 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 or interactive quantum chemistry require an immediate provision of quan-tum 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 haptic quantum chemistry. For the latter we elaborate whether a direct approach is possible by virtue of real-time quantum chemistry. Submitted for publication as a perspective article in Int. J. Quantum Chem.
Superposition and entanglement are properties of the quantum nature that suggest the construction, programming and functioning of quantum computers. Specifically, they have been imagined as a means for solving the Schrodinger equation and calculating the energy of a quantum system, i. e. doing quantum chemistry on quantum computers. It has been shown recently that this is possible in principle. We present the basic ideas of the quantum algorithm for the solution of Schrodinger´s equation and the estimation of the resources needed for a quantum computer to achieve this task.
We investigate the irreversible evolution of a small system in which a chemical reaction takes place.We have two main goals: the first requires to find an equation to produce a time-irreversible behavior,the second consists in introducing a simple exactly solvable model in order to understand basic facts in chemical kinetics.Our basic tool is the transition function counting the number of paths joining two points in the reactive coordinates system.An exact quantum Smoluchowski equation is derived for the reactive system in vacuum, in the presence of a solvent in equilibrium at any time with the reactive system a new Smoluchowski equation is obtained.The transition from a quantum regime to a classical one is discussed.The case of a reactive system not in equilibrium with its neighborhood is investigated in terms of path integral and via a partial differential function.Memory effects and closure assumptions are discussed.Using a simple potential model, the chemical rate constant is exactly calculated and questions such as the meaning of the activation energy or the physical content of the so-called prefactor are investigated.
We first give a brief, incomplete overview over historic milestones leading to the emergence of quantum chemistry, starting from John Dalton's earliest attempts to describe the atom in the early 19th century. After the formulation of the Schrödinger equation in 1926 and the first successful description of covalent bonding using the new theory, it became soon clear that the main challenge ahead was to find efficient approximations to the Schrödinger equation, as was famously stated by Paul A. M. Dirac in 1929. Since then, many quantum-chemical approximations have been introduced, with a key problem being the exponential increase of the computational cost with the system size when approaching the exact solution of the Schrödinger equation. In the second part, we will hence focus on selected techniques to overcome the scaling problem. Finally, we close with some insights into the new and challenging field of reaction network exploration, offering a glimpse into potential future directions of 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. © 2012 Wiley Periodicals, Inc.