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Caoxian Jie

Bio: Caoxian Jie is an academic researcher from University of Texas at Austin. The author has contributed to research in topics: Pericyclic reaction & Cope rearrangement. The author has an hindex of 9, co-authored 15 publications receiving 525 citations.

Papers
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TL;DR: AMI calculations for the Cope rearrangements of [3,3,2,0 2,8 ] tricyclodeca-3,7,9-triene (bullvalene; 6), (3, 3,1,0, 0 2.8 ] triene-3-7-diene (barbarbaralane; 7), and 12 derivatives of 8 were reported in this article.

43 citations


Cited by
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Journal ArticleDOI
TL;DR: In this paper, the average difference between the predicted heats of formation and experimental values for 657 compounds is 7.8 kcal/mol, and for 106 hypervalent compounds, 13.6 kcal/min.
Abstract: MNDO/AM1‐type parameters for twelve elements have been optimized using a newly developed method for optimizing parameters for semiempirical methods. With the new method, MNDO‐PM3, the average difference between the predicted heats of formation and experimental values for 657 compounds is 7.8 kcal/mol, and for 106 hypervalent compounds, 13.6 kcal/mol. For MNDO the equivalent differences are 13.9 and 75.8 kcal/mol, while those for AM1, in which MNDO parameters are used for aluminum, phosphorus, and sulfur, are 12.7 and 83.1 kcal/mol, respectively. Average errors for ionization potentials, bond angles, and dipole moments are intermediate between those for MNDO and AM1, while errors in bond lengths are slightly reduced.

3,465 citations

Journal ArticleDOI
TL;DR: Modifications that have been made to the NDDO core-core interaction term and to the method of parameter optimization have resulted in a more complete parameter optimization, called PM6, which has, in turn, allowed 70 elements to be parameterized.
Abstract: Several modifications that have been made to the NDDO core-core interaction term and to the method of parameter optimization are described. These changes have resulted in a more complete parameter optimization, called PM6, which has, in turn, allowed 70 elements to be parameterized. The average unsigned error (AUE) between calculated and reference heats of formation for 4,492 species was 8.0 kcal mol−1. For the subset of 1,373 compounds involving only the elements H, C, N, O, F, P, S, Cl, and Br, the PM6 AUE was 4.4 kcal mol−1. The equivalent AUE for other methods were: RM1: 5.0, B3LYP 6–31G*: 5.2, PM5: 5.7, PM3: 6.3, HF 6–31G*: 7.4, and AM1: 10.0 kcal mol−1. Several long-standing faults in AM1 and PM3 have been corrected and significant improvements have been made in the prediction of geometries.

3,018 citations

Journal ArticleDOI
TL;DR: This work focuses on the calculations of vibrational spectra, thermodynamic quantities, isotopic substitution effects, and force constants in a fully integrated program for the study of chemical reactions involving molecules, ions, and linear polymers using MOPAC.
Abstract: Before we start, we need a working definition for MOPAC. The following description has been used many times to describe MOPAC: MOPAC is a general-purpose, semiempirical molecular orbital program for the study of chemical reactions involving molecules, ions, and linear polymers. It implements the semiempirical Hamiltonians MNDO, AM 1, MINDO/3, and MNDOPM3, and combir_es the calculations of vibrational spectra, thermodynamic quantities, isotopic substitution effects, and force constants in a fully integrated program. Elements parameterized at the MNDO level include H, Li, Be, B, C, N, O, F, A1, Si, P, S, C1, Ge, Br, Sn, Hg, Pb, and I; at the PM3 level the elements H, C, N, O, F, A1, Si, P, S, C1, Br, and I are available. Within the electronic part of the calculation, molecular and localized orbitals, excited states up to sextets, chemical bond indices, charges, etc. are computed. Both intrinsic and dynamic reaction coordinates can be calculated. A transition-state location routine and two transition-state optimizing routines are available for studying chemical reactions.

2,422 citations

Journal ArticleDOI
TL;DR: In this article, a summary of the research work performed so far using high accuracy quantum chemical methods on polyphenolic antioxidant compounds is presented, which represents a further important contribution to elucidation of the beneficial effects on health of these substances.

928 citations