Magnetically induced ring currents in metallocenothiaporphyrins

Physical Chemistry Chemical Physics ◽

10.1039/d1cp04779e ◽

2021 ◽

Author(s):

Rashid R. Valiev ◽

Theo Kurtén ◽

Lenara Valiulina ◽

Sergey Yu. Ketkov ◽

Victor Cherepanov ◽

...

Keyword(s):

Current Density ◽

Triplet States ◽

Induced Current ◽

Susceptibility Tensor ◽

Ring Currents ◽

Singlet And Triplet States

The magnetically induced current-density susceptibility tensor (CDT) of the lowest singlet and triplet states of the metallocenothiaporphyrins, where the metal is V, Cr, Mn, Fe, Co, Ni, Mo, Tc, Ru,...

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Magnetically induced ring currents in naphthalene-fused heteroporphyrinoids

Physical Chemistry Chemical Physics ◽

10.1039/d1cp02381k ◽

2021 ◽

Author(s):

Markus Rauhalahti ◽

D Sundholm ◽

Mikael P. Johansson

Keyword(s):

Current Density ◽

Quantum Chemical ◽

Ring Current ◽

Induced Current ◽

Ring Currents ◽

Induced Currents

The magnetically induced current density of an intriguing naphthalene-fused heteroporphyrin have been studied, using the quantum-chemical, gauge-including magnetically induced currents (GIMIC) method. The ring-current strengths and current-density pathways for the...

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The B2 Structural Motif as a Tool for Modulating Ring Currents in Monocyclic Li Clusters

Chemistry ◽

10.3390/chemistry3030077 ◽

2021 ◽

Vol 3 (3) ◽

pp. 1063-1073

Author(s):

Slađana Đorđević ◽

Slavko Radenković

Keyword(s):

Current Density ◽

Structural Motif ◽

Induced Current ◽

Continuous Transformation ◽

Structural Modifications ◽

Ring Currents ◽

Current Densities

Magnetically induced current densities, calculated at the M06-2X/def2-TZVP level using the diamagnetic-zero version of the continuous transformation of origin of current density (CTOCD-DZ) method, were employed to study the aromaticity in Li3B2− and Li4B2. It was found that the Li3/Li4 rings in Li3B2− and Li4B2 remarkably resemble the monocyclic Li3+ and Li42+ clusters. Unlike the parent Li3+ and Li42+ systems that sustain negligibly weak global current density circulation, the Li3B2− and Li4B2 clusters exhibit a strong diatropic current density. The present work demonstrates how structural modifications introduced by the B2 unit can be used for modulating the current density in cyclic Li-based clusters.

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The Magnetic Response of Starphenes

Chemistry ◽

10.3390/chemistry3040099 ◽

2021 ◽

Vol 3 (4) ◽

pp. 1381-1391

Author(s):

Mesías Orozco-Ic ◽

Gabriel Merino

Keyword(s):

Magnetic Field ◽

External Magnetic Field ◽

Current Density ◽

Magnetic Response ◽

Induced Current ◽

Induced Magnetic Field ◽

Ring Currents

The aromaticity of [n]starphenes (n = 1, 4, 7, 10, 13, 16), as well as starphene-based [19]dendriphene, is addressed by calculating the magnetically induced current density and the induced magnetic field, using the pseudo-π model. When an external magnetic field is applied, these systems create diatropic currents that split into a global peripheral current surrounding the starphene skeleton and several local currents in the acene-based arms, resulting in large shielding cones above the arms. In particular, the arm currents are smaller than their linear analogs, and in general, the strengths of the ring currents tend to weaken as the starphene get larger.

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Aromaticity, π-electron delocalization, and ring currents

Pure and Applied Chemistry ◽

10.1351/pac200779060969 ◽

2007 ◽

Vol 79 (6) ◽

pp. 969-979 ◽

Cited By ~ 25

Author(s):

Patrick W. Fowler ◽

Mark Lillington ◽

Leif P. Olson

Keyword(s):

Current Density ◽

Vector Potential ◽

Ring Current ◽

Computational Cost ◽

Electron Delocalization ◽

Induced Current ◽

Simple Interpretation ◽

Cyclic System ◽

Ring Currents ◽

Highest Occupied Molecular Orbital

The magnetic criterion of aromaticity is based on the ability of a cyclic system to support a ring current. If the ring current has the diatropic sense, the system is aromatic; if the sense is paratropic, the system is antiaromatic. Attribution of aromaticity ab initio therefore reduces to the calculation and visualization of induced current density. This can be achieved at modest computational cost within the ipsocentric approach, where current density at any point in space is calculated with that point as origin of vector potential. This choice leads to accurate maps of current density and a uniquely simple interpretation in terms of nonredundant orbital contributions governed by translational and rotational selection rules. For example, four-electron diatropicity and two-electron paratropicity are predicted for delocalized forms of [4n+2]- and [4n]-annulenes, respectively. A new application to homoaromatic systems is described. Two model tris-homoaromatics, both neutral molecules, are shown to exhibit a through-space, highest occupied molecular orbital (HOMO)-dominated, four-electron ring current, in a direct analogy with the conventional "aromatic" benzene π-current.

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