Ab Initio Random Matrix Theory of Molecular Electronic Structure
- URL: http://arxiv.org/abs/2602.21299v1
- Date: Tue, 24 Feb 2026 19:02:23 GMT
- Title: Ab Initio Random Matrix Theory of Molecular Electronic Structure
- Authors: Zhen Tao, Victor Galitski,
- Abstract summary: We use ab initio electronic-structure methods to investigate random-matrix theory (RMT) universality in molecular electronic structure.<n>For generic low-symmetry geometries, the unfolded spectra of these ab initio Hamiltonians exhibit Wigner-Dyson level statistics of the Gaussian ensemble (GOE)
- Score: 2.2856320397292946
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: We use ab initio electronic-structure methods to investigate random-matrix theory (RMT) universality in molecular electronic structure. Using single-reference electronic structure methods, including Hartree-Fock, configuration-interaction singles (CIS), density functional theory, and linear-response time-dependent density-functional theory, we compute single-particle orbital energies and many-electron excitations of several representative molecules (benzene, alanine, 1-phenylethylamine, methyloxirane, and helicene chains). For generic low-symmetry geometries, the unfolded spectra of these ab initio Hamiltonians exhibit Wigner-Dyson level statistics of the Gaussian orthogonal ensemble (GOE). For extended helicene chains we explicitly restrict to bound valence excitations below the ionization threshold and still observe GOE statistics, indicating that the RMT universality is present for physical states of direct relevance to real molecules. We further explore the electric and magnetic field dependence of the molecular electronic spectra. The variance of electric polarizability (level curvature K) is predicted to be non-analytic in the magnetic field which serves as an infrared cutoff, <K^2> proportional to log(1/|B|). We observe a transition to the Gaussian unitary ensemble (GUE) by increasing the magnetic fields, although it occurs only at magnetic fields far beyond experimentally accessible scales. Our results indicate that random matrix universality provides a general framework for organizing ab initio predictions of interacting electron spectra in complex systems.
Related papers
- Direct derivation of the modified Langevin noise formalism from the canonical quantization of macroscopic electromagnetism [51.56484100374058]
We derive the exact analytical expressions for the polariton operators in terms of the canonical CQME field operators.<n>We provide a direct and rigorous derivation of the Langevin noise formalism from the canonical theory in the Schrdinger picture.
arXiv Detail & Related papers (2026-03-04T17:53:31Z) - Exploring the mechanisms of transverse relaxation of copper(II)-phthalocyanine spin qubits [9.695800379962364]
Molecular spin qubits are promising candidates for quantum technologies, but their performance is limited by decoherence arising from diverse mechanisms.<n>Here we present a systematic experimental and theoretical framework for analyzing the mechanisms of transverse relaxation in copper(II) phthalocyanine (CuPc) diluted into diamagnetic phthalocyanine hosts.<n>Our work identifies favorable values of the electron spin density for quantum applications, and provides a transferable methodology for predicting ensemble coherence times.
arXiv Detail & Related papers (2025-11-05T05:32:56Z) - Twisted light drives chiral excitations of interacting electrons in nanostructures with magnetic field [0.0]
Twisted light (TL) provides a powerful tool for driving symmetry resolved transitions in quantum confined nanostructures.<n>We study a realistic model where a TL pulse excites two interacting electrons in a nanostructure under a perpendicular magnetic field.
arXiv Detail & Related papers (2025-08-25T20:44:58Z) - Spin-Electric Control of Individual Molecules on Surfaces [0.0]
We present spin-electric coupling (SEC) for two molecular spin systems, iron phthalocyanine (FePc) and Fe-FePc complexes, adsorbed on a surface.<n>We show that the spin dynamics can be tuned, demonstrating a pathway towards electrically controlled quantum operation.
arXiv Detail & Related papers (2025-07-18T07:03:05Z) - Generalized many-body perturbation theory for the electron correlation energy: multi-reference random phase approximation via diagrammatic resummation [6.34014022599321]
Many-body perturbation theory (MBPT) based on Green's functions and Feynman diagrams provides a fundamental theoretical framework for emphab initio computational approaches.<n>However, perturbation expansion often fails in systems with strong multi-reference characters.<n>We develop a diagrammatic multi-reference of MBPT for computing correlation energies of strongly correlated systems.
arXiv Detail & Related papers (2024-10-30T13:08:57Z) - Non-Uniform Magnetic Fields for Single-Electron Control [0.0]
A gauge-invariant formulation of the Wigner equation for general electromagnetic fields has been proposed.
We generalize this equation to include a general, non-uniform electric field and a linear, non-uniform magnetic field.
This has led to explore a new type of transport inside electronic waveguides based on snake trajectories.
arXiv Detail & Related papers (2023-11-10T19:05:54Z) - Sensing of magnetic field effects in radical-pair reactions using a
quantum sensor [50.591267188664666]
Magnetic field effects (MFE) in certain chemical reactions have been well established in the last five decades.
We employ elaborate and realistic models of radical-pairs, considering its coupling to the local spin environment and the sensor.
For two model systems, we derive signals of MFE detectable even in the weak coupling regime between radical-pair and NV quantum sensor.
arXiv Detail & Related papers (2022-09-28T12:56:15Z) - Strong-Field Molecular Ionization Beyond The Single Active Electron
Approximation [0.0]
We study signals of the single ionization of $H$ under a strong near-infrared (NIR) four-cycle, linearly-polarized laser pulse of varying intensity.
We give an interpretation of this in terms of a Resonance-Enhanced-Multiphoton Ionization (REMPI) mechanism with interfering resonances resulting from excited electronic states.
arXiv Detail & Related papers (2022-09-15T09:49:14Z) - Calculating non-linear response functions for multi-dimensional
electronic spectroscopy using dyadic non-Markovian quantum state diffusion [68.8204255655161]
We present a methodology for simulating multi-dimensional electronic spectra of molecular aggregates with coupling electronic excitation to a structured environment.
A crucial aspect of our approach is that we propagate the NMQSD equation in a doubled system Hilbert space but with the same noise.
arXiv Detail & Related papers (2022-07-06T15:30:38Z) - Relativistic aspects of orbital and magnetic anisotropies in the
chemical bonding and structure of lanthanide molecules [60.17174832243075]
We study the electronic and ro-vibrational states of heavy homonuclear lanthanide Er2 and Tm2 molecules by applying state-of-the-art relativistic methods.
We were able to obtain reliable spin-orbit and correlation-induced splittings between the 91 Er2 and 36 Tm2 electronic potentials dissociating to two ground-state atoms.
arXiv Detail & Related papers (2021-07-06T15:34:00Z) - Controlled coherent dynamics of [VO(TPP)], a prototype molecular nuclear
qudit with an electronic ancilla [50.002949299918136]
We show that [VO(TPP)] (vanadyl tetraphenylporphyrinate) is a promising system suitable to implement quantum computation algorithms.
It embeds an electronic spin 1/2 coupled through hyperfine interaction to a nuclear spin 7/2, both characterized by remarkable coherence.
arXiv Detail & Related papers (2021-03-15T21:38:41Z) - General quantum-mechanical solution for twisted electrons in a uniform
magnetic field [68.8204255655161]
A theory of twisted (and other structured) paraxial electrons in a uniform magnetic field is developed.
The observable effect of a different behavior of relativistic Laguerre-Gauss beams with opposite directions of the orbital angular momentum penetrating from the free space into a magnetic field is predicted.
arXiv Detail & Related papers (2020-05-13T16:35:10Z) - Quantum coherent spin-electric control in a molecular nanomagnet at
clock transitions [57.50861918173065]
Electrical control of spins at the nanoscale offers architectural advantages in spintronics.
Recent demonstrations of electric-field (E-field) sensitivities in molecular spin materials are tantalising.
E-field sensitivities reported so far are rather weak, prompting the question of how to design molecules with stronger spin-electric couplings.
arXiv Detail & Related papers (2020-05-03T09:27:31Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.