Presentation of a new index for estimation of aromaticity in halo‐ and cyanobenzenes: The role of potential energy in aromaticity. Issue 2 (26th August 2013)

• Record Type: Journal Article
• Authors: Ebrahimi, Ali; Mostafavi, Najmeh; Karimi, Pouya
• Is Part Of: International journal of quantum chemistry. Volume 114:Issue 2(2014:Jan. 15)
• Page Start: 154
• Page End: 161
• Publication Date: 2013-08-26
• Subjects: Quantum chemistry -- Periodicals; 541.28
• DOI: 10.1002/qua.24534
• Languages: English
• ISSNs: 0020-7608

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <p>A linear correlation has been obtained between average values of Hamiltonian kinetic energy ( <alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pgg3zftkv67" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math display="inline" altimg="urn:x-wiley:00207608:media:qua24534:qua24534-math-0001" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi mathvariant="normal">K</mml:mi><mml:mrow><mml:mo stretchy="true">(</mml:mo><mml:mi mathvariant="normal">r</mml:mi><mml:mo stretchy="true">)</mml:mo></mml:mrow></mml:mrow></mml:math></alternatives>) and potential energy ( <alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pgg3zftkv9w" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math display="inline" altimg="urn:x-wiley:00207608:media:qua24534:qua24534-math-0002" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi mathvariant="normal">V</mml:mi><mml:mrow><mml:mo stretchy="true">(</mml:mo><mml:mi mathvariant="normal">r</mml:mi><mml:mo stretchy="true">)</mml:mo></mml:mrow></mml:mrow></mml:math></alternatives>) calculated at the bond critical points using atoms in molecules method. This relation was used to introduce a new index ( <alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pgg3zftkv7s" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math display="inline" altimg="urn:x-wiley:00207608:media:qua24534:qua24534-math-0003" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi mathvariant="normal">M</mml:mi><mml:mrow><mml:mo stretchy="true">(</mml:mo><mml:mi mathvariant="normal">r</mml:mi><mml:mo stretchy="true">)</mml:mo></mml:mrow></mml:mrow></mml:math></alternatives>) for estimation of aromaticity in halo‐ and cyanobenzenes. Potential energy has different terms such as attraction between nuclei and electrons, also repulsion of electrons which affect the inertia and mobility of electrons, respectively. Therefore, contribution of potential energy in this relation must be controlled. Contribution of potential energy in aromaticity has been managed using a fitting parameter. This parameter was obtained by fitting the aromaticity stabilization energy data with values of aromaticity calculated by <alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pgg3zftkvdj" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math display="inline" altimg="urn:x-wiley:00207608:media:qua24534:qua24534-math-0004" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi mathvariant="normal">M</mml:mi><mml:mrow><mml:mo stretchy="true">(</mml:mo><mml:mi mathvariant="normal">r</mml:mi><mml:mo stretchy="true">)</mml:mo></mml:mrow></mml:mrow></mml:math></alternatives> index for halo‐ and cyanobenzenes. The contribution of potential energy in <alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pgg3zftkvf3" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math display="inline" altimg="urn:x-wiley:00207608:media:qua24534:qua24534-math-0005" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi mathvariant="normal">M</mml:mi><mml:mrow><mml:mo stretchy="true">(</mml:mo><mml:mi mathvariant="normal">r</mml:mi><mml:mo stretchy="true">)</mml:mo></mml:mrow></mml:mrow></mml:math></alternatives> index is complete when molecule is nonaromatic and is negligible when molecule is antiaromatic. Indeed, molecule is aromatic when contribution of potential energy in <alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pgg3zftkvgn" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math display="inline" altimg="urn:x-wiley:00207608:media:qua24534:qua24534-math-0006" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi mathvariant="normal">M</mml:mi><mml:mrow><mml:mo stretchy="true">(</mml:mo><mml:mi mathvariant="normal">r</mml:mi><mml:mo stretchy="true">)</mml:mo></mml:mrow></mml:mrow></mml:math></alternatives> index lies between above limits. © 2013 Wiley Periodicals, Inc.</p> </abstract>