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Das Buch ist eine Einführung in die Chemische Thermodynamik und Kinetik für Chemiker in Bachelor-Studiengängen. Dabei wurde besonderes Augenmerk auf Verständlichkeit, gute Lesbarkeit und übersichtliche Darstellung gelegt.   Im Mittelpunkt steht das Verständnis der Grundlagen der Thermodynamik und Kinetik. Dazu werden die zentralen Konzepte wie Energie und Entropie in gut nachvollziehbarer und konsistenter Weise eingeführt, ihre Entstehungsgeschichte und Bedeutung wird auf anschauliche Weise diskutiert. Wie funktioniert die naturwissenschaftliche Beschreibung komplexer Phänomene, warum ist sie so erfolgreich und was bedeutet das alles? Diese Fragen werden im Grundlagenteil des Buches adressiert und in den Anwendungen auf chemische Fragestellungen systematisch aufgenommen. Die Anwendungen auf Mischungsvorgänge, chemische Reaktivität, Phasenübergänge und Elektrochemie zeigen, wie die physikalische Chemie zum grundlegenden Verständnis chemischer Vorgänge beiträgt. Die notwendigen mathematischen Grundlagen werden verständlich und systematisch eingeführt, der Aufbau des Buches ist so gestaltet, dass die physikalisch-chemischen Problemstellungen im Zentrum stehen.                                     Der Autor Prof. Dr. Marcus Elstner ist seit 2009 Professor am Institut für Physikalische Chemie des Karlsruher Instituts für Technologie (KIT). Nach seiner Promotion in theoretischer Physik und einem Postdoc-Aufenthalt an der Harvard-Universität (1999–2000) war er u. a. Professor für theoretische Chemie an der TU Braunschweig (2006–2009). In seiner Forschung untersucht er die (physikalisch-chemischen) Eigenschaften von komplexen Makromolekülen mithilfe von Computersimulationen, welche auf den grundlegenden Konzepten und Methoden der physikalischen Chemie beruhen.

Physical chemistry. --- Thermodynamics. --- Physical Chemistry.

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Chemistry, Organic. --- Physical chemistry --- Physical chemistry

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COLLOIDS --- PHYSICAL CHEMISTRY --- COLLOIDS --- PHYSICAL CHEMISTRY

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Chemistry --- Physical Chemistry

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In order to contribute more knowledge on atmospheric chemistry of VOCs, this work focuses on kinetics of the reactions between OH and five (substituted) alcohols (hydroxyacetone, 1-propanol, 2-butanol, 2-methyl-2-butanol, and 1,2-ethanediol). The bimolecular rate coefficients of these reactions were measured over the temperature range 290 550 K and over the pressure range 5 100 Torr He by using a Pulsed Laser Photolysis Pulsed Laser Induced Fluorescence (PLP-PLIF) system. The obtained results, over a wide range of temperatures at 50 Torr He, show unusual temperature dependences of the ratecoefficients. In the OH + hydroxyacetone reaction, below ~380 K the rate constant (k1) was found tobe negatively dependent on temperature. However, at temperatures greater than ~ 410 K k1 shows a positive trend. For the reaction of 1-propanol, non-Arrhenius behavior was revealed. At temperature in the range 296 400 K, the rate coefficient (k2) is independent of temperature, with an average value of 5.6 × 1012 cm3 molecule1 s1. Above 400 K, k2 positively depends on temperature and can be expressed by the Arrhenius equation k2(T) = 1.08 × 1011 exp(247/T) cm3 molecule1 s1. In the case of 2-butanol, the transition of k3 from a negative dependence to a positive dependence occurs around 400 K. No temperature dependence of the rate coefficient (k4) was observed in the reaction between OH and 2-methyl-2-butanol. In the reaction of OH and 1,2-ethanediol, k5 is negatively dependent on temperature below ~ 420 K, and switches to a positive dependence above 420 K. The rate coefficients k1, k2, k3, k5 were determined at different pressures in the range 5 100 Torr He. k1, k3, k5 were found to decrease when decreasing pressure below 30 Torr, whereas k2 was nearly constant in the range 10 50 Torr. These unusual temperature and pressure dependences of the rate coefficients k1, k3, and k5 can be ascribed tothe particular mechanism of the title reactions, which all proceed through a pre-reactive complex (PRC) and via a submerged transition state. In this work, this mechanism, which has been reported by previous theoretical studies, is discussed at length for the OH + hydroxyacetone reaction and confirmed bythe experimental evidence provided. To our knowledge, it is the first time that the pressure dependence that can be expected for such mechanisms was indeed observed. At very low pressures, only PRCs with fixed energies above the reactants, and hence well above the TS level, are present, and the only fates are (1) fast re-dissociation over the very loose variational bottleneck back to the reactants, and (2) slower forward reaction well above the tight transition state. The net forward rate will therefore be much slower than the initial capture rate. At high pressures and low temperatures, pre-reactive complexes are rapidly stabilized by collision and result in a thermal Boltzmann energy distribution that leads to a large steady-state population of PRCs in the well. Hence, the total rate coefficient at high pressures is described by (1) passage over the TS barrier of that proportion of PRCs having energies between the reactants level and the transition state level and (2) tunneling of that fraction of PRCs lying lower the transition state zero-point energy. This combination results in a higher rate than at low pressures and a negative temperature dependence of the rate coefficient at low temperatures. At higher temperatures, tunneling becomes less important; the population of PRCs above the transition state level increases, and hence also the rate coefficient. However, in the reactions of 1-propanol and 2-methyl-2-butanol, energies of transition states are expected to be higher than reactants. Hence, at high pressures and low temperatures the enhanced flux by the tunneling effect is offset by a lower flux over the barrier, rendering the rate coefficients for 1-propanol and 2-methyl-2-butanol nearly constant with temperature (over temperature range 237 - 400 K). The last part of this work was aimed at comparing our experimental results and some previous results for the reactions between OH and the five selected compounds with rate coefficient predictions using the Structure-Activity Relationships (SARs) developed by Atkinson (Chem. Rev., 1986, 86, 69 201) then upgraded by (1) Kwok and Atkinson (Atmos. Environ., 1995, 29 (4), 1685 1695), and (2) Bethel and Atkinson (Int. J. Chem. Kinet., 2001, 33 (5), 310 - 316. Although SARs yielded some good predictions at room temperature, they could not capture the temperature and pressure dependences (with the exception of the temperature dependence of the rate coefficient for the reaction OH + hydroxyacetone at high temperature). The limitation of using these SARs is partially explained by neglecting long-range chemical interaction of the OH group, especially the formation of pre-reactive complexes between the OH radical and the alcohols.

544 --- Academic collection --- Physical chemistry --- Theses --- 544 Physical chemistry