Pseudo Jahn–Teller effect in distortion and restoration of planar configurations of tetra-heterocyclic 1,2-diazetes C2N2E4, E = H, F, Cl, Br

Ilkhani, Ali Reza; Gorinchoy, Natalia; Берсукер, И. Б.

doi:10.1016/j.chemphys.2015.07.015

Cited by 26 publications

(22 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The results revealed that ten electrons and eight active orbitals which was composed the CAS (10,8) active space is appropriate in under considered C 2 Y 3 Z 2 series. Additionally, the CAS(10,8) results comparison to the smaller CAS(4,3), CAS (6,6), and CAS (8,8) and lager CAS (12,12) active spaces that previously have been applied in similar PJTE origin studies; 22,24,27,31 was proved that CAS(10,8) active space sufficiently is good in present study. From Table 2 is also appeared that the eight orbitals included 2a 1 , 2b 1 , 2b 2 , and 2a 2 were being contributed to the electron excitations of the C 2 Y 3 Z 2 series.…”

Section: Active Space In Sa-casscf Calculationmentioning

confidence: 62%

“…[15][16][17][18][19][20][21][22][23][24][25][26][27] Restoring planarity in the systems that are puckered from their planar configurations due to the symmetry breaking phenomenon has been investigated through the PJTE. To do so, their planar configuration restores ether by coordinating two anions, cations, or rings up and down to the nonplanar systems [28][29][30] or influences the parameters of the PJTE instability by removing or adding electrons; 31 they show that symmetry breaking phenomenon is suppressed in the folded systems. In other applications of the PJTE, the origin of puckering in tricyclic compounds to a pseudo Jahn-Teller (PJT) problem has been traced.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

The symmetry breaking phenomenon in 1,2,3-trioxolene and C2Y3Z2 (Z= O, S, Se, Te, Z= H, F) compounds: a pseudo Jahn−Teller origin study

Ilkhani¹

2017

Quim. Nova

View full text Add to dashboard Cite

Section: Active Space In Sa-casscf Calculationmentioning

confidence: 62%

Section: Introductionmentioning

confidence: 99%

The symmetry breaking phenomenon in 1,2,3-trioxolene and C2Y3Z2 (Z= O, S, Se, Te, Z= H, F) compounds: a pseudo Jahn−Teller origin study

Ilkhani¹

2017

Quim. Nova

View full text Add to dashboard Cite

“…The next group of molecules includes 1,2-dichalcogenins, 1,2-C 4 X 2 L 4 , with X = O, S, Se, Te and L = H, F [10], two tricyclic species C 6 S 8 and with L = H, F, Cl, Br [17]. The planar configuration of these systems is unstable with respect to the twisting coordinate of a 2 symmetry that leads to a puckered equilibrium structure of C 2 symmetry.…”

Section: Introductionmentioning

confidence: 99%

Pseudo Jahn-Teller Effect in Puckering and Planarization of Heterocyclic Compounds

Gorinchoy¹

2018

IJOC

View full text Add to dashboard Cite

The goal of this brief partly review paper is to summarize the results of the works published over the last few years regarding the origin of the out-of-plane distortions (puckering) of heterocyclic compounds. In all the papers devoted to this problem, it is shown that the instability of planar configurations of heterocyclic molecules leading to symmetry breaking and distortions is induced by the pseudo Jahn-Teller effect (PJTE). Special attention in this work is paid to the mechanism of suppression and enhancement of the PJTE distortions of heterocycles by oxidation, reduction, and chemical substitutions. It is demonstrated that oxidation of 1,4-dithiine containing compounds leads to suppression of the PJTE and to restoration of their planar nuclear configurations. An example of a dibenzo[1,2]dithiine molecule is used to demonstrate the mechanism of enhancement of the PJTE by reduction. It is shown that the reduction of the neutral C 12 H 8 S 2 molecule up to the dianion (C 12 H 8 S 2) 2− enhances the PJTE, followed by the S-S bond cleavage and significant structural distortions of the system. The change of the PJTE by chemical substitutions, accompanied either by puckering or by planarization of heterocyclic compounds, is discussed using as examples 1,4-ditinine and its S-oxygenated derivatives.

show abstract

“…More importantly, based on the PJTE formulation, structural change could be manipulated in the ways of adjusting the energy gaps between the related excited states or PJTE parameters to effectively suppress or enhance the PJTE intensity. According to these rules, many efficient strategies can be taken, such as removing or adding electrons, chemical substitutions, or weak coordination with other atoms or functional groups …”

Section: Introductionmentioning

confidence: 99%

Pseudo Jahn–Teller origin tracking for symmetry breaking in halogenabenzene: How can a bird fly?

Wang

Liu

Zheng

2018

Int J of Quantum Chemistry

View full text Add to dashboard Cite

The cyclic iodabenzene molecule (CH) 5 I was first introduced and characterized as planar configuration and zwitterionic valence structure by Glukhovtsev in 1991. Recently, it caused researchers' great interest due to the theoretical discovery of a stable bird-like structure by Hoffmann et al. in 2017 which has similar electronic structure and charge distribution as wellknown Meisenheimer complex C 6 H − 7 . Inspired by this, we continue to tell the halogenabenzene story by revealing the origin of the bird-like structure and understanding how the electronic behavior affects the geometrical symmetry for a molecule. By combining the Pseudo Jahn-Teller effect (PJTE) theory with the ab initio calculations for halogenabenzenes (CH) 5 X (X = F, Cl, Br, I) and C 6 H − 7 , it is illustrated that the vibronic coupling of 1 A 1 ground state and 1 B 1 excited states with C 2v planar structure along the out-of-plane b 1 distortion triggers the symmetry breaking of planar configuration to form a preferred bird-like structure. This interpretation can be also applied to explain their different stabilization energies by analyzing numerically the energy gaps of coupled electronic states and PJTE vibronic coupling parameters. Taking use of the PJTE formulation above, we also tracked the origin of restoring to be planar for (CH) 5 X 2+ cation, as well as their isoelectronic species (CH) 5 O + and (CH) 5 N, and suggests an effective strategy to stabilize the planar configuration for halogenabenzenes. K E Y W O R D S excited state, halogenabenzene, pseudo Jahn-Teller effect, symmetry breaking, vibronic coupling 1 | INTRODUCTIONWhen referring to halogen-substituted benzene compounds, most of attention has been paid to the cases that hydrogen atoms in different positions of benzene are substituted for halogen atoms, such as C 6 H 5 X [1][2][3][4] and C 6 H 4 X 2 or C 6 X 6 [2-7] (X = F, Cl, Br, I). In contrast, the systems in which the carbon atom is replaced by halogen atom have been rarely reported. The cyclic (CH) 5 I molecule, called iodabenzene, was firstly introduced by Glukhovtsev in 1991 and found to show a planar configuration with 8π electron system based on the semiempirical AM1 and MNDO calculations. [8] More recently, Hoffmann and his coworkers performed more accurate DFT and MP2 calculations on iodabenzene and obtained a stable bird-like minimum structure, which is expected optimistically to be detected and isolated in experiment. [9] It was also described that iodabenzene and its analogues (CH) 5 X (X = F, Cl, Br) have the similar geometric configuration and zwitterionic valence electronic structure to the famous Meisenheimer complexes. [10,11] Besides the neutral halogenabenzene molecules, the cation (CH) 5 X 2+ (X = F, Cl, Br, I), as well as their iso-valence electronic pyrylium cation (CH) 5 O + and pyridine (CH) 5 N, also attracted great interest in literatures. [12][13][14][15] As very common chemical reagents, (CH) 5 O + and (CH) 5 N are applied extensively in the field of organic chemistry. The (CH) 5 O + is used ...

show abstract

Pseudo Jahn–Teller effect in distortion and restoration of planar configurations of tetra-heterocyclic 1,2-diazetes C2N2E4, E = H, F, Cl, Br

Cited by 26 publications

References 25 publications

The symmetry breaking phenomenon in 1,2,3-trioxolene and C2Y3Z2 (Z= O, S, Se, Te, Z= H, F) compounds: a pseudo Jahn−Teller origin study

The symmetry breaking phenomenon in 1,2,3-trioxolene and C2Y3Z2 (Z= O, S, Se, Te, Z= H, F) compounds: a pseudo Jahn−Teller origin study

Pseudo Jahn-Teller Effect in Puckering and Planarization of Heterocyclic Compounds

Pseudo Jahn–Teller origin tracking for symmetry breaking in halogenabenzene: How can a bird fly?

Contact Info

Product

Resources

About