Cross‐Conjugation and Quantum Interference

Solomon, Gemma C.

doi:10.1002/9783527671182.ch11

Cited by 6 publications

(5 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Looking at the orbital interaction between a linker unit and the π-conjugated skeleton will result in an important insight into the strength of electronic coupling, which can significantly affect the occurrence of QI. , Figure a,b shows a perturbation MO (PMO) analysis , of 1,4-sulfur-terminated butadiene (1,4-STB) and 1,3-STB in terms of the union of butadiene with two S atoms, each bearing a p−π orbital. Details of the PMO method are given in the Section 4 of the SI.…”

Section: Resultsmentioning

confidence: 99%

Frontier Orbital Perspective for Quantum Interference in Alternant and Nonalternant Hydrocarbons

Tsuji

Yoshizawa

2017

J. Phys. Chem. C

View full text Add to dashboard Cite

The wave-particle duality of electrons gives rise to quantum interference (QI) in single molecular devices. A significant challenge to be addressed in molecular electronics is to further develop chemical intuition to understand and predict QI features. In this study, an orbital rule is markedly ameliorated so that it can capture the manifestation of QI not only in alternant hydrocarbons but also in nonalternant ones. The orbital-based prediction about the occurrence of QI in a nonalternant hydrocarbon shows good agreement with experimental results. A simple perturbation theoretic line of reasoning suggests that frontier orbital phase and splitting play a pivotal role in QI phenomena.

show abstract

Section: Resultsmentioning

confidence: 99%

Frontier Orbital Perspective for Quantum Interference in Alternant and Nonalternant Hydrocarbons

Tsuji

Yoshizawa

2017

J. Phys. Chem. C

View full text Add to dashboard Cite

show abstract

“…The key question of this work is how cross-conjugation and electronegativity affect QI features. 11 , 20 , 52 , 55 , 56 Based on our experimental observations and calculations, we assert that destructive QI induced by cross-conjugation is highly sensitive to the functional groups that induce the cross-conjugation and that quinones are, therefore, a poor testbed for tuning QI effects (beyond switching them on and off 57 ) because their strong electron-withdrawing nature places a deep, destructive feature near E F irrespective of other functional groups (in our case, two fused thiophene rings barely make a difference). Comparing a quinone to a hydrocarbon also compares HOPS-mediated tunneling to LUPS-mediated tunneling between molecules with significantly different band-gaps and absolute frontier orbital energies.…”

Section: Discussionmentioning

confidence: 99%

Controlling destructive quantum interference in tunneling junctions comprising self-assembled monolayers via bond topology and functional groups

Zhang

Soni

et al. 2018

Chem. Sci.

View full text Add to dashboard Cite

show abstract

“…The final variation in acyclic π-delocalization is cross conjugation, which is the focus of active research in organic electronics. , The lattice with extended cross conjugation is constructed by stacking two layers of isolated double bonds that run perpendicular to the zig-zag direction (Figure ). These are interspersed with two layers of epoxide that are placed similarly on the graphene lattice, forming a rectangular unit cell ( Z = 4).…”

Section: Resultsmentioning

confidence: 99%

Topological Impact of Delocalization on the Stability and Band Gap of Partially Oxidized Graphene

2023

View full text Add to dashboard Cite

Strategic perturbations on the graphene framework to inflict a tunable energy band gap promises intelligent electronics that are smaller, faster, flexible, and much more efficient than silicon. Despite different chemical schemes, a clear scalable strategy for micromanaging the band gap is lagging. Since conductivity arises from the delocalized π-electrons, chemical intuition suggests that selective saturation of some sp 2 carbons will allow strategic control over the band gap. However, the logical cognition of different 2D π-delocalization topologies is complex. Their impact on the thermodynamic stability and band gap remains unknown. Using partially oxidized graphene with its facile and reversible epoxides, we show that delocalization overwhelmingly influences the nature of the frontier bands. Organic electronic effects like hyperconjugation, conjugation, aromaticity, etc. can be used effectively to understand the impact of delocalization. By keeping a constant C 4 O stoichiometry, the relative stability of various πdelocalization topologies is directly assessed without resorting to resonance energy concepts. Our results demonstrate that >C�C< and aromatic sextets are the two fundamental blocks resulting in a large band gap in isolation. Extending the delocalization across these units will increase the stability at the expense of the band gap. The band gap is directly related to the extent of bond alternation within the π-framework, with forced single/double bonds causing the large gap. Furthermore, it also establishes the ground rules for the thermodynamic stability associated with the π-delocalization in 2D systems. We anticipate that our findings will provide the heuristic guidance for designing partially saturated graphene with the desired band gap and stability using chemical intuition.

show abstract

Cross‐Conjugation and Quantum Interference

Cited by 6 publications

References 15 publications

Frontier Orbital Perspective for Quantum Interference in Alternant and Nonalternant Hydrocarbons

Frontier Orbital Perspective for Quantum Interference in Alternant and Nonalternant Hydrocarbons

Controlling destructive quantum interference in tunneling junctions comprising self-assembled monolayers via bond topology and functional groups

Topological Impact of Delocalization on the Stability and Band Gap of Partially Oxidized Graphene

Contact Info

Product

Resources

About