Luminescent Organic Triplet Diradicals as Optically Addressable Molecular Qubits

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 27, 2024

Optical-spin interfaces that enable the photoinitialization, coherent microwave manipulation, and optical read-out of ground state spins have been studied extensively in solid-state defects such as diamond nitrogen vacancy (NV) centers are promising for quantum information science applications. Molecular bits (qubits) offer many advantages over spin through synthetic control their properties scalability into well-defined multiqubit arrays. In this work, we report an optical-spin interface organic molecular qubit consisting two luminescent tris(2,4,6-trichlorophenyl)methyl (TTM) radicals connected via

Language: Английский

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A Luminescent Stable Triarylmethyl Diradical with an Axially Chiral Spacer

Chemistry - A European Journal, Journal Year: 2025, Volume and Issue: unknown

Published: March 6, 2025

Two units of a highly stable luminescent triarylmethyl radical (PyBTM) were bridged using chiral octahydrobinaphthyl moiety, resulting in diradical with sufficient stability to enable the measurement its chiroptical properties. To synthesize this diradical, novel boronic ester precursor, αH-PyBTM-B(Epin), was designed. The use precursor significantly improved yield and streamlined preparation radical-substituted molecules. photoluminescence quantum (PLQY) measured be 10 % chloroform. Furthermore, both circular dichroism (CD) circularly polarized luminescence (CPL) successfully observed.

Language: Английский

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Enhancing the Optically Detected Magnetic Resonance Signal of Organic Molecular Qubits

ACS Central Science, Journal Year: 2025, Volume and Issue: 11(1), P. 116 - 126

Published: Jan. 3, 2025

In quantum information science and sensing, electron spins are often purified into a specific polarization through an optical-spin interface, process known as optically detected magnetic resonance (ODMR). Diamond-NV centers transition metals both excellent platforms for these so-called color centers, while metal-free molecular analogues also gaining popularity their extended lifetimes, milder environmental impacts, reduced costs. our earlier attempt at designing such organic high-spin π-diradicals, we proposed to spin-polarize by shelving triplet MS = ±1 populations singlets. This was recently verified experiments albeit with low ODMR contrasts of <1% temperatures above 5 K. this work, propose improve the signal moving singlet back 0 sublevel, true carbon-based analogue NV center. Our proposal is based upon transition-orbital group-theoretical analyses beyond-nearest-neighbor spin–orbit couplings, which further confirmed ab initio calculations realistic trityl-based radical dimer. Microkinetic point toward high around 30% under experimentally feasible conditions, stark improvement from previous works. Finally, in quest ground-state addressable spin qubits, exemplify how symmetry-based design avoids Zeeman-induced singlet–triplet mixings, setting scene realizing qubit gates.

Language: Английский

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On the Meaning of De‐Excitations in Time‐Dependent Density Functional Theory Computations

Journal of Computational Chemistry, Journal Year: 2025, Volume and Issue: 46(8)

Published: March 25, 2025

De-excitations play a prominent role within the mathematical formalism of time-dependent density functional theory (TDDFT) and other excited-state response methods. However, their physical meaning remains largely unexplored poorly understood. It is purpose this work to shed new light on issue. The main thesis developed here that de-excitations are not peculiarity TDDFT but they more fundamental property underlying wave functions reflecting how electrons excited between partially occupied orbitals. paraquinodimethane (pQDM) molecule chosen as convenient model system whose open-shell character can be modulated via twisting its methylene groups. Using one-electron transition matrix rigorous basis for our analysis, we highlight qualitative quantitative parallels in way reflected multireference function computations. As physically observable consequence, lowering dipole moment derives from destructive interference excitation de-excitation contributions. In summary, hope will formal practical aspects regarding application computations, especially diradicaloid systems.

Language: Английский

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1,1′-Biolympicenyl: A Stable Non-Kekulé Diradical with a Small Singlet and Triplet Energy Gap

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(38), P. 26454 - 26465

Published: Sept. 10, 2024

Dimerization of delocalized polycyclic hydrocarbon radicals is a simple and versatile method to create diradicals with tailored electronic structures accessible high-spin states. However, the synthesis challenging, stability issue remains concern. In this study, we present stable non-Kekulé 1,1'-biolympicenyl diradical

Language: Английский

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Classification and quantitative characterisation of the excited states of π-conjugated diradicals

Faraday Discussions, Journal Year: 2024, Volume and Issue: 254, P. 107 - 129

Published: Jan. 1, 2024

Diradicals are of high current interest as emerging materials for next generation optoelectronic applications. To tune their excited-state properties it would be greatly beneficial to have a detailed understanding the wave functions different states involved but this endeavour is hampered by formal and practical barriers. tackle these challenges, we present analysis well concrete results on diradical excited states. We start with investigation available two-orbital two-electron model viewed from both valence-bond molecular orbital perspectives. highlight presence zwitterionic illustrate connections found in closed-shell molecules. Subsequently, introduce protocols analysing realistic multireference computations applying

Language: Английский

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