2014英特爾ISEF獲獎作品摘要 化學 Intel Finalist Abstract Chemistry

獲獎作品基本信息

年份	2014
學科	化學 Chemistry
國家/州	United States of America

獲獎作品名稱

Factors that Influence Energies of Simple Hydrocarbons

獲獎作品摘要

Although several models have been proposed to account for the varying stabilities of alkanes, the ability of these models to fit experimental data remains controversial. The work presented here focuses on evaluating the abilities of three models to describe the energy differences of alkanes, thereby providing insight into the factors that are the most consequential to hydrocarbons' relative stabilities and leading to the proposal of the vicinal interactions model (VIM). In contrast to older models that generally lack theoretical support, the VIM is justified by natural bond orbital (NBO) analysis confirming that vicinal, antiperiplanar bond-bond and bond-antibond interactions are the most consequential. The VIM is a fairly simple additivity scheme based on bond enthalpies and vicinal, antiperiplanar bond pair interactions. The VIM was compared to the localized bond model (LBM) and geminal interactions model (GIM). Energy parameters for each model were fitted to best represent the atomization enthalpies (AE) of the C1-C6 alkanes, calculated by the Gaussian electronic structure program. Parameter fittings yielded chi squared values for the LBM, GIM, and VIM of 15.26, 12.04, 7.68 respectively. As anticipated, the LBM failed to account for differing AEs as it attributed no significance to any factors other than CC and CH bond enthalpies. The GIM, although exhibiting an improvement over the LBM, failed to describe the AEs of alkane conformers. The proposed VIM, on the other hand, generated unique AEs for each C1-C6 alkanes.? The results of this study strongly support the VIM as a new model for understanding the differing stabilities of alkanes.

 

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ISEF 簡介

英特爾國際科學與工程大獎賽，簡稱 "ISEF"，由美國 Society for Science and the Public（科學和公共服務協會）主辦，英特爾公司冠名贊助，是全球規模最大、等級最高的中學生的科研科創賽事。ISEF 的學術活動學科包括了所有數學、自然科學、工程的全部領域和部分社會科學。ISEF 素有全球青少年科學學術活動的“世界杯”之美譽，旨在鼓勵學生團隊協作，開拓創新，長期專一深入地研究自己感興趣的課題。

學科簡介：化學 Chemistry

Studies exploring the science of the composition, structure, properties, and reactions of matter not involving biochemical systems.

Subcategories:

Analytical Chemistry?(ANC):?The study of the separation, identification, and quantification of the chemical components of materials.

Computational Chemistry?(COM):?A study that applies the discipline and techniques of computer science and mathematics to solve large and complex problems in Chemistry.

Environmental Chemistry?(ENV):?The study of chemical species in the natural environment, including the effects of human activities, such as the design of products and processes that reduce or eliminate the use or generation of hazardous substances.

Inorganic Chemistry?(INO):?The study of the properties and reactions of inorganic and organometallic compounds.

Materials Chemistry?(MAT):?The chemical study of the design, synthesis and properties of substances, including condensed phases (solids, liquids, polymers) and interfaces, with a useful or potentially useful function, such as catalysis or solar energy.

Organic Chemistry?(ORG):?The study of carbon-containing compounds, including hydrocarbons and their derivatives.

Physical Chemistry?(PHC):?The study of the fundamental physical basis of chemical systems and processes, including chemical kinetics, chemical thermodynamics, electrochemistry, photochemistry, spectroscopy, statistical mechanics and astro-chemistry.

Other?(OTH):?Studies that cannot be assigned to one of the above subcategories. If the project involves multiple subcategories, the principal subcategory should be chosen instead of Other.