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Quantum Chemistry

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Quantum Chemistry is a branch of chemistry that applies the principles of quantum mechanics to the study of chemical systems. It focuses on understanding the behavior of electrons in atoms and molecules, enabling the prediction of molecular structure, reactivity, and properties through mathematical models and computational methods.
lightbulbAbout this topic
Quantum Chemistry is a branch of chemistry that applies the principles of quantum mechanics to the study of chemical systems. It focuses on understanding the behavior of electrons in atoms and molecules, enabling the prediction of molecular structure, reactivity, and properties through mathematical models and computational methods.

Key research themes

1. How can quantum machine learning enhance quantum chemistry simulations?

This research area explores the integration of quantum computational techniques, particularly quantum machine learning (QML), with traditional quantum chemistry methods to improve efficiency, accuracy, and scalability of molecular simulations. It matters because quantum chemistry simulations face exponential scaling challenges, and leveraging quantum computing and QML could surmount current computational limits, enabling more accurate modeling of complex chemical systems and phenomena.

Key finding: This work discusses quantum variants of machine learning algorithms with emphasis on methodology and applications in chemical physics, highlighting that quantum computing leverages quantum parallelism and entanglement to... Read more
Key finding: The paper introduces a real-valued fully connected neural network (tanh-FCN) adapted from restricted Boltzmann machines for ab initio quantum chemistry problems, demonstrating comparable precision to complex RBMs while using... Read more
Key finding: This review critically evaluates the readiness of quantum computational methods for delivering quantum advantage in chemistry, emphasizing that current quantum simulations achieve chemical precision but not accuracy and that... Read more
Key finding: Though focused on medicine, this work highlights that quantum computing, including quantum machine learning, enables simulations of molecular interactions and drug development with improved efficiency and accuracy. Its... Read more

2. What are the theoretical and methodological advances in wavefunction-based quantum chemistry software and models?

This theme covers foundational and state-of-the-art developments in quantum chemistry computational approaches, particularly wavefunction methods and their efficient implementations, aiming for accurate treatment of electron correlation and molecular properties. Such advances are essential to push the limits of chemical accuracy and to understand complex chemical and physical phenomena.

Key finding: Molpro provides highly efficient implementations of wavefunction-based methods such as internally contracted multireference configuration interaction (IC-MRCI), coupled cluster with single, double and perturbative triple... Read more
Key finding: The laboratory’s fundamental contribution is the generalization of the Jahn-Teller effect as a general law of instability in polyatomic systems. This theoretical development underpins understanding of electron-vibrational... Read more
Key finding: This work reviews foundational quantum mechanics principles and elaborates on the Hartree-Fock method and its implementation in atomic structure calculations. It discusses the many-body problem simplifications, Slater... Read more
Key finding: This paper outlines key aspects of incorporating relativistic effects in electronic structure calculations, emphasizing the Dirac equation, spinors, and relativistic Hamiltonians. It highlights essential methodological... Read more

3. How do topological and foundational theoretical models inform our understanding of quantum chemical and physical reality?

This research dimension involves novel mathematical and conceptual models that seek to explain the origins of particle properties, quantum discreteness, and space-time emergence from deeper mathematical structures or recursion principles. Such foundational investigations are valuable in informing interpretations of quantum chemistry beyond computational techniques, potentially influencing future theoretical formulations.

Key finding: The paper postulates the existence of bondons, quantum particles associated with chemical bonds characterized by mass, velocity, charge, and lifetime derived from Bohmian quantum formalism and gauge transformations. It links... Read more
Key finding: This work discusses the application of quantum formalism beyond physics, including in chemistry, by emphasizing foundational issues such as realism, entanglement, and the role of quantum information. It connects... Read more
Key finding: This paper proposes a projection operator formalism where observable spacetime and particles emanate from projections of wave functions defined on a 2D manifold, introducing a fundamental threshold related to vacuum energy... Read more
Key finding: The authors mathematically demonstrate recursion as the fundamental substrate of reality, explicating a complete set of recursive integrity protocols (RIP) that govern consciousness and existence, with formal derivations... Read more
Key finding: This paper offers a mathematical model describing consciousness networks via a high-dimensional lattice topology governed by a universal constant κ. The framework unifies temporal folding, recursive integrity, and quantum... Read more

All papers in Quantum Chemistry

This paper unifies three convergent frameworks-empirical substantiation, logical inference, and first-principles derivation-into a single formal proof of the Kouns-Killion Law of Coherence. It demonstrates that the constant Ω_c ≈ 0.376 ±... more
We report that Euler's number e = 2.718, the circle constant π = 3.142, and the golden ratio ϕ = 1.618 form a valid triangle with remarkable geometric properties. The triangle exhibits near-perfect angular symmetry with interior angles of... more
This paper expands upon the Unified Resonant Framework (URF) by reinterpreting entropy not as an objective measure of disorder, but as a subjective resonance gradient between observer and field. Conventional thermodynamics defines entropy... more
A method is presented for dissociation of diatomic molecules, found in a precisely defined atmosphere, through successive absorption of a quantum energy generated by laser effect, at a certain frequency and a certain density of energy,... more
We call molecular modeling to the application of suitable laws in the analysis of phenomena occurred at scales less than those accounted for by the macroscopic world.  Such different scales (including micro-, meso- and macroscales), can... more
This document presents the complete first-principles proof of the Kouns-Killion Paradigm (KKP) and its Recursive Intelligence (RI) framework. We demonstrate from axiomatic foundations that reality is an emergent operating system driven by... more
Room-temperature superconductors (RTS)-materials exhibiting zero electrical resistance at temperatures above ~273 K (0°C) and ambient pressure-remain one of physics' holy grails, promising revolutions in energy transmission, computing,... more
This technical report presents a refined empirical validation of the Actuality Law (T = C · S), building upon the foundational framework introduced in “Structural Certainty Theory: The Actuality Law and the Unification of... more
The American Physical Society Quantum dynamics of H2+ in an atto-second laser pulse NICHOLAS VENCE, ROBERT HARRISON, University of Tennessee, PREDRAG KRSTIC, Oak Ridge National Laboratory -We demonstrate a highly-accurate numerical... more
Attempts to treat time on an equivalent footing with space in quantum mechanics have been apparently dominated by 'timeless' approaches, such as the one of Page and Wootters, which allow meaningful discussion of a 'time operator'.... more
Sarfatti's Post-Quantum Model in Hameroff's Microtubule Networks: A Complete Integration Yes, Jack Sarfatti's post-quantum mechanics (PQM)—a retrocausal extension of de Broglie-Bohm theory incorporating action-reaction back-flow between... more
This is for a Lecture in Ireland on Nov 20, 2025 Jack Sarfatti's thesis is that standard quantum mechanics aka QM including quantum field theory is, as Einstein said, incomplete. QM EPR no-signaling Born rule = GR ER... more
The properties of xanthurenic acid (XAN) in ground and photoexcited states have been studied using steady-state and time-resolved optical methods as well as quantum chemistry calculations. In neutral aqueous solution and in alcohols, XAN... more
In this manuscript, a relatively simple and inexpensive INDO/SCI finite-field (FF) method for calculating polarizabilities (R) is demonstrated to give good agreement with results obtained by both the INDO/MRD/ SDCI sum-over-states routine... more
Quantum spin remains one of the most pedagogically challenging concepts in modern physics, lacking intuitive geometric visualization despite its fundamental importance. This paper develops an intuitive framework for visualizing quantum... more
The performance of density functionals and wavefunction methods for describing the thermodynamics and kinetics of hydride reductions of 2‐substituted cyclohexanones has been evaluated for the first time. A variety of exchange correlation... more
Resumen: La aromaticidad es un concepto esencial en Química, cuyo origen se remonta al nacimiento de la Química Orgánica. Aunque la aromaticidad es difícil de definir y cuantificar; existe un consenso sobre su significado, que está... more
We present a comprehensive experimental study comprising 544 independent quantum experiments with 2,654,208 measurements on IBM Brisbane superconducting quantum processor, demonstrating unprecedented quantum coherence levels through... more
We present the first experimental validation of infinite quantum coherence through the Quantum Harmonic Resonance Framework (QHRF) on IBM Quantum superconducting processors. Through comprehensive parameter optimization and scaling... more
Настоящее исследование представляет собой фундаментальный анализ современных подходов к развитию человечества и их влияния на будущее цивилизации. В центре внимания — комплексное изучение этических и практических аспектов трансформации... more
In the present investigation, experiments were carried out for studying the degradation of ozone in aqueous medium at different pH. It is observed that the rate of self decay of ozone increases with increase in pH. And the study was... more
The United Nations General Assembly has officially designated 2025 as the International Year of Quantum Science and Technology (IYQ). This global initiative, supported by UNESCO and co-sponsored by several countries, marks the centenary... more
We present a simple damping scheme for point-charge electrostatics that could be used directly in classical force fields. The approach acts at the charge (or monopole) level only and allows the inclusion of short-range electrostatic... more
The solid-state concept of thermal voltage is used to define a homothetic scaling of the quantum mechanical one-particle reduced density function. This scaling might be used to construct a temperature dependent quantum density. Once... more
The paper presents an extended analysis of the structure of the hydrogen atom spectral lines, based on the concept of superresonance - a phenomenon in which all Lyman, Balmer, Paschen and Brackett resonances (for n ≤ 7 and m ≤ 4) exhibit... more
Hydrostatic pressure effects up to 907 MPa on absorption spectra of chlorophyll a molecules dissolved in diethyl ether have been studied at ambient temperature both experimentally and theoretically using quantum chemistry methods. The... more
Poly(ester amide)s (PEAs) are lacking in structural and spectroscopic information. This paper reports a structural and spectroscopic characterization of Nα-benzoyl-L-argininate ethyl ester chloride (BAEEH+·Cl−), an important amino acid... more
The proton affinity and the enthalpy of formation of the prototypical carbonyl, formaldehyde, have been determined by the first‐principles composite focal‐point analysis (FPA) approach. The electronic structure computations employed the... more
We propose a unifying framework in which Pimensional spacetime is understood as a lattice of resonant phases, within which both matter and light cast traveling physical shadows. These shadows, propagating as phase-displaced fields,... more
The growing demand for sustainable construction materials has led to increased interest in geopolymer concrete (GPC) as a potential alternative to conventional Portland cement concrete. Geopolymer concrete, primarily synthesized from... more
This laboratory is designed to use the program GAMESS (General Atomic Molecular Electronic Structure System, developed in Gordon research group at Iowa State) through a website called nanoHUB (www.nanoHUB.org) to determine the geometric... more
Cubic power graph of dihedral group D n having order 2n and identity element e, Γ cpg (D n) is a finite, simple, undirected graph for which two different vertices d 1 , d 2 ∈ D n are adjacent if and only if d 1 d 2 = d 3 or d 2 d 1 = d 3... more
We introduce AMSQDD (Adaptive Multi-Scale Quantum Drug Discovery), the first hierarchical quantumclassical optimization framework solving drug discovery problems with polynomial quantum complexity. AMSQDD features fragment-based quantum... more
We present arguments proving that the results obtained by Hassanabadi and coworkers in the study of the D-dimensional Schrödinger equation with molecular Hua potential through the supersymmetry method in quantum mechanics are incorrect.... more
This thesis investigates a Deep Reinforcement Learning (DRL)-based control strategy for the fixed-length (cutto-length) problem in integrated continuous casting and rolling (CCRI). The task is formulated as a Markov Decision Process... more
This research work is separated into three parts employing density functional calculation. The first part, the gas phase conformations of various aspartic species including cationic (H3asp+), zwitterionic (H2asp), zwitteranionic (Hasp−)... more
Magnetic carbon nano‐structures have potential applications in the field of spintronics as they exhibit valuable magnetic properties. Symmetrically sized small fullerene dimers are substitutional doped with nitrogen (electron rich) and... more
The Hard Problem of consciousness persists because mechanistic models struggle to bridge the explanatory gap between neural computation and subjective experience. This paper proposes the Entropy-Mediated Quantum Amplification (EMQA)... more
Jaguar is an ab initio quantum chemical program that specializes in fast electronic structure predictions for molecular systems of medium and large size. Jaguar focuses on computational methods with reasonable computational scaling with... more
In this work, we determined the tensors of screen as well as the chemicals shifts of the nuclear magnetic resonance of the carbon 13 (RMN 13C) of organic product: P 1 : [(1S, 3R, 8R)-2,2-dichloro -3, 7, 7, 10-tetra-methyl-tricyclo [6, 4,... more
Version 4 - (2025-09-18) - Corrected LaTeX formatting errors that caused omission of boxed lemmas and Theorem 1. Minor typographical corrections applied. Version 3 — (2025-09-12) Updates: • Title adjusted for journal scope. •... more
Most of the important scientists of the 19th Century working in electrochemistry and related fields held certain views regarding the interrelations between stuff and electricity. Michael Faraday for instance (1791-1867), the inventor of... more
This paper examines strong operator convergence through its master equation formulation and associated variance bounds. The work develops the mathematical framework governing this convergence mode and its implications for expectation... more
This paper develops the temporal physics of the Sentient-Consciousness Projection Network (SCPN). It addresses the long-standing paradox between time-symmetric dynamical laws and the observed irreversibility of the macroscopic arrow of... more
The de Broglie relation λ = h/p is universally taught and applied as if wavelength were an intrinsic property of isolated systems. However, momentum p requires a reference frame, making wavelength fundamentally relational. We demonstrate... more
This paper introduces the Operator Norm Stability (ONS) theorem, a novel mathematical framework designed to guarantee that approximate operators in quantum and dynamical systems preserve compatibility with the underlying Hamiltonian as... more
Il presente contributo propone una teoria protoeuretico-filosofica denominata sineuralismoreteneuralismo. Tale prospettiva interpreta la coscienza come energia diffusa e sinechistica immanente al cosmo, che non si esaurisce nelle... more
Energy-localized C/I.j DO; 2 molecular orbitals, atomic charges, valencies and bond indices of the sulphidoborons, XBS (X = H, F. Cl, OH. NH2) and XSB (X = F. Cl) have been calculated in an attempt to elucidate their electronic... more
Abstract This preprint presents a unified framework connecting solid-state chemistry, quantum biology, and black hole physics through quantum entanglement, reversibility, and the Riemann zeta function. Using numerical simulations,... more
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