Ring Currents in Large [4n + 2]-Annulenes

Alessandro Soncini; Patrick W. Fowler; Leonardus W. Jenneskens

doi:10.1002/chin.200416285

On the generation of electronic ring currents under vibronic coupling effects

The Journal of Chemical Physics ◽

10.1063/5.0031389 ◽

2020 ◽

Vol 153 (22) ◽

pp. 224308

Author(s):

Krishna Reddy Nandipati ◽

Oriol Vendrell

Keyword(s):

Vibronic Coupling ◽

Coupling Effects ◽

Ring Currents

Download Full-text

Coherent Ring Currents in Chiral Aromatic Molecules Induced by Linearly Polarized UV Laser Pulses

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.543.381 ◽

2013 ◽

Vol 543 ◽

pp. 381-384 ◽

Cited By ~ 2

Author(s):

Manabu Kanno ◽

Hirohiko Koho ◽

Hirobumi Mineo ◽

Sheng Hsien Lin ◽

Yuichi Fujimura

Keyword(s):

Aromatic Ring ◽

Quantum Dynamics ◽

Ring Current ◽

Molecular System ◽

Laser Pulses ◽

Uv Laser ◽

Aromatic Molecules ◽

Ring Currents ◽

Linearly Polarized ◽

Coherent Ring

In recent years, laser control of electrons in molecular system and condensed matter has attracted considerable attention with rapid progress in laser science and technology [. In particular, control of π-electron rotation in photo-induced chiral aromatic molecules has potential utility to the next-generation ultrafast switching devices. In this paper, we present a fundamental principle of generation of ultrafast coherent ring currents and the control in photo-induced aromatic molecules. This is based on quantum dynamics simulations of π-electron rotations and preparation of unidirectional angular momentum by ultrashort UV laser pulses properly designed. For this purpose, we adopt 2,5-dichloro [(3,6) pyrazinophane (DCPH) fixed on a surface, which is a real chiral aromatic molecule with plane chirality. Here π electrons can be rotated along the aromatic ring clockwise or counterclockwise by irradiation of a linearly polarized laser pulse with the properly designed photon polarization direction and the coherent ring current with the definite direction along the aromatic ring is prepared. This is contrast to ordinary ring current in an achiral aromatic ring molecule with degenerate electronic excited state, which is prepared by a circularly polarized laser [2]. In this case, π electrons rotate along the Z-axis of the laboratory coordinates, while for the present case electrons rotate along the z-axis in molecular Cartesian coordinates. It should be noted that signals originated from the coherent ring currents prepared by linearly polarized ultrashort UV lasers are specific to the chiral molecule of interest.

Download Full-text

Untersuchung des Druckaufbaus einer stationären, magnetfeldstabilisierten Helium-Entladung mit Hilfe magnetischer Messungen

Zeitschrift für Naturforschung A ◽

10.1515/zna-1967-1023 ◽

1967 ◽

Vol 22 (10) ◽

pp. 1599-1612 ◽

Cited By ~ 2

Author(s):

Otto Klüber

Keyword(s):

Magnetic Field ◽

Magnetic Flux ◽

Plasma Column ◽

Ambipolar Diffusion ◽

Nernst Effect ◽

Thermomagnetic Effect ◽

Field Coil ◽

Neutral Gas ◽

Ring Currents ◽

The Magnetic Field

A stationary discharge is produced bya current flowing parallel to the magnetic field ofa cylindrical coil. In the region where the field is homogeneous the pressure in the plasma column is much higher than that in the surrounding neutral gas. This is mainly caused by diamagnetic ring currents, as is shown by measuring the magnetic flux due to these currents. Two effects are primarily responsible for the ring currents in this region: The already known effect of the ambipolar diffusion across the magnetic field anda thermomagnetic effect, called NERNST effect, whose influence on the pressure build-up ofa plasma has not been investigated hitherto. Other phenomena causing ring currents occur in the plasma near the coil ends and outside the field coil.

Download Full-text

Functional group introduction and aromatic unit variation in a set of π‑conjugated macrocycles: revealing the central role of local and global aromaticity

Organic Chemistry Frontiers ◽

10.1039/d1qo00901j ◽

2021 ◽

Author(s):

Martina Rimmele ◽

Wojciech Nogala ◽

Maryam Seif-Eddine ◽

Maxie Roessler ◽

Martin Heeney ◽

...

Keyword(s):

Functional Group ◽

Ring Currents ◽

Conjugated Macrocycles

π-Conjugated macrocycles are molecules with unique properties that are increasingly exploited for applications and the question of whether they can sustain global aromatic or antiaromatic ring currents is particularly intriguing....

Download Full-text

Canonical orbital contributions to the magnetic fields induced by global and local diatropic and paratropic ring currents

Journal of Computational Chemistry ◽

10.1002/jcc.24917 ◽

2017 ◽

Vol 38 (30) ◽

pp. 2594-2604 ◽

Cited By ~ 10

Author(s):

Nickolas D. Charistos ◽

Anastasios G. Papadopoulos ◽

Thomas A. Nikopoulos ◽

Alvaro Muñoz-Castro ◽

Michael P. Sigalas

Keyword(s):

Magnetic Fields ◽

Ring Currents ◽

Global And Local

Download Full-text

FRONTIER-ORBITAL RING CURRENTS AND THE ANNULENE ANALOGY

Polycyclic Aromatic Compounds ◽

10.1080/10406630490468540 ◽

2004 ◽

Vol 24 (4-5) ◽

pp. 353-366 ◽

Cited By ~ 4

Author(s):

P. W. Fowler ◽

A. Soncini

Keyword(s):

Frontier Orbital ◽

Ring Currents

Download Full-text

Survival and extinction of delocalised ring currents in clamped benzenes

Chemical Communications ◽

10.1039/b106651j ◽

2001 ◽

pp. 2386-2387 ◽

Cited By ~ 38

Author(s):

Patrick W. Fowler ◽

Remco W. A. Havenith ◽

Leonardus W. Jenneskens ◽

Alessandro Soncini ◽

Erich Steiner

Keyword(s):

Ring Currents

Download Full-text

Polariton Ring Currents and Circular Dichroism of Mg-porphyrin in a Chiral Cavity

Chemical Science ◽

10.1039/d1sc04341b ◽

2022 ◽

Author(s):

Shichao Sun ◽

Bing Gu ◽

S. Mukamel

Keyword(s):

Circular Dichroism ◽

Time Reversal ◽

Optical Cavity ◽

Polarized Light ◽

Time Reversal Symmetry ◽

Porphyrin Molecule ◽

Ring Currents ◽

Linearly Polarized ◽

Circular Dichroïsm

By placing a Mg-porphyrin molecule in a chiral optical cavity, time reversal symmetry is broken, thus generating polariton ring currents even with linearly polarized light. These currents induce a circular...

Download Full-text