Valence isomers of benzene and their relationship to the isoelectronic isomers of arsenic molecule (As6)

Warren, Daniel; Gimarc, Benjamin M.; Zhao, Ming

doi:10.1021/ic00082a015

Cited by 30 publications

(18 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We had some inkling of this result from calculated strain energies in phosphorus clusters where we also found the four-membered ring to have a larger strain energy than the three-membered ring.5 A study of arsenic clusters leads to the same conclusion. 6 As an additional confirmation, we calculated strain energies for the oxygen rings 0,,7,8 which we found to follow the same trend as S, rings.…”

Section: Introductionsupporting

confidence: 67%

Strain Energies of (NH)n Rings, n = 3-8

Zhao¹,

Gimarc²

1994

J. Phys. Chem.

Self Cite

View full text Add to dashboard Cite

Strain energies are related to energy changes for processes that open rings into chains. In the earlier papers of this series, we introduced an s-homodesmotic reaction which converts rings into chains while preserving the valence environment around each atom and conserving bond types. In this paper, we report geometry optimized ab initio S C F MO calculations for (NH), rings and H(NH),H chains performed with the 6-31G** basis set at R H F and MP2 levels of theory. We use these results to calculate strain energies for (NH), rings as energy differences for s-homodesmotic reactions. The bond type and valence environment conservation properties of these reactions allow at least some of the effects of basis set and electron correlation errors to cancel as differences are taken between calculated energies of products and reactants. We find that for (NH), the strain energy is a maximum for n = 4, as it is for the series S, and 0,. For the cycloalkanes, (CHZ),, ring strain is greatest for n = 3. The (NH), strain energies are smallest for n = 5 and 6 and large again for n = 7 and 8. We rationalize the relative energies of different ring conformations in various ring classes on the basis of the gauche effect, a preference for conformations in which lone pairs of electrons on adjacent atoms are approximately 90° apart.

show abstract

Section: Introductionsupporting

confidence: 67%

Strain Energies of (NH)n Rings, n = 3-8

Zhao¹,

Gimarc²

1994

J. Phys. Chem.

Self Cite

View full text Add to dashboard Cite

show abstract

“…In a previous work, the analogy of As 6 cluster and valence isomers of benzene was investigated by Warren et al using restricted Hartree-Fock method with 6-311G ** basis. 25 They also found that the energy of D 3h structure ͓Fig. 2͑a͔͒ is lower than that of C 2v isomer ͓Fig.…”

Section: B Asmentioning

confidence: 99%

“…2͑d͒ was investigated in Ref. 25 with ⌬E = 0.92 eV, while ⌬E is 0.70 eV from present PBE calculation. The planar hexgonal six-membered ring ͑6MR͒ with D 6h symmetry in Fig.…”

Section: B Asmentioning

confidence: 99%

“…19 Most theoretical studies also considered small As n clusters ͑n ഛ 6͒. [20][21][22][23][24][25][26][27] In a Hartree Fock Moller-Plesset 2nd ͑HF͒/ ͑MP2͒ treatment, a cagelike structure with D 3d symmetry was considered for As 12 and a dodecahedral conformation with I h symmetry was explored for As 20 . 27 Low-energy configurations were obtained for As n , n ഛ 11, using simulated annealing and the local density approximation ͑LDA͒ within the density-functional theory ͑DFT͒.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Density-functional study of small and medium-sizedAsnclusters up ton=28

Zhao¹,

Zhou²,

Chen³

et al. 2006

Phys. Rev. B

View full text Add to dashboard Cite

Results of an all-electron density functional theory study of structural and electronic properties of As n clusters in the size range n ഛ 28 are presented and discussed. The atomization energies for most even-sized As n ͑n ജ 8͒ clusters with closed-shell electronic configurations are higher than that of As 4 , indicating their relative stability upon dissociation into As 4 fragments. Similar to P n clusters, supercluster structures based on As 4 , As 6 , As 8 units and As 2 bridge were found to be dominant for the larger As n with n ജ 14. The size-dependent physical properties of clusters such as atomization energies, ionization potentials, and molecular orbital gaps have been discussed.

show abstract

“…The planar hexagons of P 6 [114] and As 6 [115] have the highest energies of the five valence isomers.…”

Section: Pentazole Rn 5 and Hexazine Nmentioning

confidence: 99%

Orbitals in Inorganic Chemistry: Metal Rings and Clusters, Hydronitrogens, and Heterocyles

Inagaki

2009

Orbitals in Chemistry

View full text Add to dashboard Cite

A chemical orbital theory is useful in inorganic chemistry. Some applications are described for understanding and designing of inorganic molecules. Among the topics included are: (1) valence electron rules to predict stabilities of three- and four-membered ring metals and for those of regular octahedral M(6) metal clusters solely by counting the number of valence electrons; (2) pentagon stability (stability of five- relative to six-membered rings in some classes of molecules), predicted and applied for understanding and designing saturated molecules of group XV elements; (3) properties of unsaturated hydronitrogens N( m )H( n ) in contrast to those of hydrocarbons C( m )H( n ); (4) unusually short nonbonded distances between metal atoms in cyclic molecules.

show abstract

Valence isomers of benzene and their relationship to the isoelectronic isomers of arsenic molecule (As6)

Cited by 30 publications

References 0 publications

Strain Energies of (NH)n Rings, n = 3-8

Strain Energies of (NH)n Rings, n = 3-8

Density-functional study of small and medium-sizedAsnclusters up ton=28

Orbitals in Inorganic Chemistry: Metal Rings and Clusters, Hydronitrogens, and Heterocyles

Contact Info

Product

Resources

About