東華大學圖書館 |

Language: English

Help

回圖書館首頁

手機版館藏查詢

Back

Switch To: Labeled | MARC Mode | ISBD

Linked to FindBook

Google Book

Amazon

博客來

Computational Methods Applied to the Study of the Structure, Spectra, and Reactivity of Small Organic Molecules.

Record Type:	Electronic resources : Monograph/item
Title/Author:	Computational Methods Applied to the Study of the Structure, Spectra, and Reactivity of Small Organic Molecules./
Author:	Owen, Andrew N.
Description:	1 online resource (424 pages)
Notes:	Source: Dissertations Abstracts International, Volume: 84-02, Section: B.
Contained By:	Dissertations Abstracts International84-02B.
Subject:	Computational chemistry. -
Online resource:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=29327979click for full text (PQDT)
ISBN:	9798841766650

Computational Methods Applied to the Study of the Structure, Spectra, and Reactivity of Small Organic Molecules.
Owen, Andrew N.

Computational Methods Applied to the Study of the Structure, Spectra, and Reactivity of Small Organic Molecules. - 1 online resource (424 pages)

Source: Dissertations Abstracts International, Volume: 84-02, Section: B.

Thesis (Ph.D.)--The University of Wisconsin - Madison, 2022.

Includes bibliographical references

Quantum chemical ab initio methods are applied to a variety of systems to support experimental efforts and to model reactions in harsh environments. High level geometry optimizations and vibrational frequency calculations are combined with experimental fits of rotational spectra to obtain highly precise semi-experimental equilibrium structures (reSE) of hydrazoic acid (HN3) and pyridazine (ortho C4H4N2 analog of benzene). Purely theoretical equilibrium structures (re) are obtained for both HN3 and pyridazine and require corrections to account for the size of the basis set, for electron correlation, for relativity, and for the Born-Oppenheimer approximation. These corrections bring the theoretical re structures into agreement with the experimentally obtained reSE structures. Further, application of a novel analysis of the reSE structure determination (xrefiteration) provides confidence that these reSE structures are highly accurate, in addition to being highly precise. A combination of density function theory (DFT) and ab initio methods are used to model reactions in several systems. The diastereoselectivity observed in the synthesis of 1-cyano-1,3-butadienes is satisfactorily explained by the computational investigation of the conformational interconversion of the proposed intermediates. A purely theoretical investigation of the reactions of highly unsaturated carbon chains (CnH2) utilizes spin-flip methods to describe the resulting radical species and intervening reactions and finds that the products of [4+2] cycloadditions are more likely to retain the initially formed six-membered ring than are the products of [2+2] cycloadditions to retain the initially formed four-membered ring.Finally, we describe our application of established theory to derive formulas that can be used for the prediction of the vibration-rotation coupling constants that are used to fit the rotational spectra of coupled vibrational states. Our initial results predict the experimentally determined values of Fbc for the coupled-state fits of benzonitrile to within 15%, and the formulas can be used to explain the origin of the proportional relationship of the coupling constants that was observed. The derivation also gives rise to the α corrections to the rotational constants in agreement with previous derivations. Furthermore, the preliminary results of a computer algebra program we are developing are presented and discussed.

Electronic reproduction.
Ann Arbor, Mich. :
ProQuest,
2023

Mode of access: World Wide Web

ISBN: 9798841766650Subjects--Topical Terms:

3350019
Computational chemistry.
Subjects--Index Terms:

CyanobutadieneIndex Terms--Genre/Form:

542853
Electronic books.

Computational Methods Applied to the Study of the Structure, Spectra, and Reactivity of Small Organic Molecules.
LDR:03932nmm a2200409K 4500 001 2363453
005 20231127093406.5
006 m o d
007 cr mn ---uuuuu
008 241011s2022 xx obm 000 0 eng d
020 $a 9798841766650
035 $a (MiAaPQ)AAI29327979
035 $a AAI29327979
040 $a MiAaPQ $b eng $c MiAaPQ $d NTU
100 1 $a Owen, Andrew N. $3 3704215
245 1 0 $a Computational Methods Applied to the Study of the Structure, Spectra, and Reactivity of Small Organic Molecules.
264 0 $c 2022
300 $a 1 online resource (424 pages)
336 $a text $b txt $2 rdacontent
337 $a computer $b c $2 rdamedia
338 $a online resource $b cr $2 rdacarrier
500 $a Source: Dissertations Abstracts International, Volume: 84-02, Section: B.
500 $a Advisor: McMahon, Robert J.;Woods, Robert C.
502 $a Thesis (Ph.D.)--The University of Wisconsin - Madison, 2022.
504 $a Includes bibliographical references
520 $a Quantum chemical ab initio methods are applied to a variety of systems to support experimental efforts and to model reactions in harsh environments. High level geometry optimizations and vibrational frequency calculations are combined with experimental fits of rotational spectra to obtain highly precise semi-experimental equilibrium structures (reSE) of hydrazoic acid (HN3) and pyridazine (ortho C4H4N2 analog of benzene). Purely theoretical equilibrium structures (re) are obtained for both HN3 and pyridazine and require corrections to account for the size of the basis set, for electron correlation, for relativity, and for the Born-Oppenheimer approximation. These corrections bring the theoretical re structures into agreement with the experimentally obtained reSE structures. Further, application of a novel analysis of the reSE structure determination (xrefiteration) provides confidence that these reSE structures are highly accurate, in addition to being highly precise. A combination of density function theory (DFT) and ab initio methods are used to model reactions in several systems. The diastereoselectivity observed in the synthesis of 1-cyano-1,3-butadienes is satisfactorily explained by the computational investigation of the conformational interconversion of the proposed intermediates. A purely theoretical investigation of the reactions of highly unsaturated carbon chains (CnH2) utilizes spin-flip methods to describe the resulting radical species and intervening reactions and finds that the products of [4+2] cycloadditions are more likely to retain the initially formed six-membered ring than are the products of [2+2] cycloadditions to retain the initially formed four-membered ring.Finally, we describe our application of established theory to derive formulas that can be used for the prediction of the vibration-rotation coupling constants that are used to fit the rotational spectra of coupled vibrational states. Our initial results predict the experimentally determined values of Fbc for the coupled-state fits of benzonitrile to within 15%, and the formulas can be used to explain the origin of the proportional relationship of the coupling constants that was observed. The derivation also gives rise to the α corrections to the rotational constants in agreement with previous derivations. Furthermore, the preliminary results of a computer algebra program we are developing are presented and discussed.
533 $a Electronic reproduction. $b Ann Arbor, Mich. : $c ProQuest, $d 2023
538 $a Mode of access: World Wide Web
650 4 $a Computational chemistry. $3 3350019
650 4 $a Molecular chemistry. $3 1071612
650 4 $a Physical chemistry. $3 1981412
653 $a Cyanobutadiene
653 $a Hydrazoic acid
653 $a Pyridazine
653 $a Rotational spectroscopy
653 $a Structure determination
653 $a Vibration rotation coupling
655 7 $a Electronic books. $2 lcsh $3 542853
690 $a 0219
690 $a 0431
690 $a 0494
710 2 $a ProQuest Information and Learning Co. $3 783688
710 2 $a The University of Wisconsin - Madison. $b Chemistry. $3 2049906
773 0 $t Dissertations Abstracts International $g 84-02B.
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=29327979 $z click for full text (PQDT)