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Stuttgart, Germany

The University of Stuttgart is a university located in Stuttgart, Germany. It was founded in 1829 and is organized in 10 faculties.It is one of the top nine leading technical universities in Germany with highly ranked programs in civil, mechanical, industrial and electrical engineering.The University of Stuttgart is especially known for its excellent reputation in the fields of advanced automotive engineering, efficient industrial and automated manufacturing, process engineering, aerospace engineering and activity-based costing. The academic tradition of the University of Stuttgart goes back to its probably most famous graduate student: Gottlieb Daimler, the Inventor of the automobile.Along with the Technical University of Munich, the Technical University of Darmstadt and Karlsruhe Institute of Technology, it represents one of the four members of the South German Axis of Advanced Engineering and Management. These four universities, in combination with RWTH Aachen are the top five universities of the aforementioned TU9. Wikipedia.

Kaim W.,University of Stuttgart
Inorganic Chemistry | Year: 2011

The potential of redox-active ligands to behave "noninnocently" in transition-metal coordination compounds is reflected with respect to various aspects and situations. These include the question of establishing "correct" oxidation states, the identification and characterization of differently charged radical ligands, the listing of structural and other consequences of ligand redox reactions, and the distinction between barrierless delocalized "resonance" cases Mn/Ln ↔ Mn+1Ln-1 versus separated valence tautomer equilibrium situations Mn/Ln ⇌ Mn+1Ln-1. Further ambivalence arises for dinuclear systems with radical bridge M n(μ-L•)Mn versus mixed-valent alternatives M n+1(μ-L-)Mn, for noninnocent ligand-bridged coordination compounds of higher nuclearity such as (μ3-L)M 3, (μ4-L)M4, (μ-L)4M 4, or coordination polymers. Conversely, the presence of more than one noninnocently behaving ligand at a single transition-metal site in situations such as Ln-M-Ln-1 or L•-M-L• may give rise to corresponding ligand-to-ligand interaction phenomena (charge transfer, electron hopping, and spin-spin coupling) and to redox-induced electron transfer with counterintuitive oxidation-state changes. The relationships of noninnocent ligand behavior with excited-state descriptions and perspectives regarding material properties and single-electron or multielectron reactivity are also illustrated briefly. © 2011 American Chemical Society. Source

Knizia G.,University of Stuttgart
Journal of Chemical Theory and Computation | Year: 2013

Modern quantum chemistry can make quantitative predictions on an immense array of chemical systems. However, the interpretation of those predictions is often complicated by the complex wave function expansions used. Here we show that an exceptionally simple algebraic construction allows for defining atomic core and valence orbitals, polarized by the molecular environment, which can exactly represent self-consistent field wave functions. This construction provides an unbiased and direct connection between quantum chemistry and empirical chemical concepts, and can be used, for example, to calculate the nature of bonding in molecules, in chemical terms, from first principles. In particular, we find consistency with electronegativities (χ), C 1s core-level shifts, resonance substituent parameters (σR), Lewis structures, and oxidation states of transition-metal complexes. © 2013 American Chemical Society. Source

Kaim W.,University of Stuttgart
Coordination Chemistry Reviews | Year: 2011

The near-infrared (750-2500 nm) region of the electromagnetic spectrum has received enhanced attention recently from the areas of atmospheric and analytical chemistry, from communications technology, and from the side of medical applications. Coordination compounds absorbing strongly in this region can do so because of extended ligand π systems, mixed valency, or the presence of radical ion ligands. The background of such low-energy absorptivity is provided, together with examples from the inorganic and organometallic coordination chemistry of Mo, Mn, Fe, Ru, Os, Rh, Ir, Pt and Cu. © 2011 Elsevier B.V. Source

Seifert U.,University of Stuttgart
Reports on Progress in Physics | Year: 2012

Stochastic thermodynamics as reviewed here systematically provides a framework for extending the notions of classical thermodynamics such as work, heat and entropy production to the level of individual trajectories of well-defined non-equilibrium ensembles. It applies whenever a non-equilibrium process is still coupled to one (or several) heat bath(s) of constant temperature. Paradigmatic systems are single colloidal particles in time-dependent laser traps, polymers in external flow, enzymes and molecular motors in single molecule assays, small biochemical networks and thermoelectric devices involving single electron transport. For such systems, a first-law like energy balance can be identified along fluctuating trajectories. For a basic Markovian dynamics implemented either on the continuum level with Langevin equations or on a discrete set of states as a master equation, thermodynamic consistency imposes a local-detailed balance constraint on noise and rates, respectively. Various integral and detailed fluctuation theorems, which are derived here in a unifying approach from one master theorem, constrain the probability distributions for work, heat and entropy production depending on the nature of the system and the choice of non-equilibrium conditions. For non-equilibrium steady states, particularly strong results hold like a generalized fluctuation-dissipation theorem involving entropy production. Ramifications and applications of these concepts include optimal driving between specified states in finite time, the role of measurement-based feedback processes and the relation between dissipation and irreversibility. Efficiency and, in particular, efficiency at maximum power can be discussed systematically beyond the linear response regime for two classes of molecular machines, isothermal ones such as molecular motors, and heat engines such as thermoelectric devices, using a common framework based on a cycle decomposition of entropy production. © 2012 IOP Publishing Ltd. Source

Seifert U.,University of Stuttgart
Physical Review Letters | Year: 2011

We consider nanosized artificial or biological machines working in steady state enforced by imposing nonequilibrium concentrations of solutes or by applying external forces, torques, or electric fields. For unicyclic and strongly coupled multicyclic machines, efficiency at maximum power is not bounded by the linear response value 1/2. For strong driving, it can even approach the thermodynamic limit 1. Quite generally, such machines fall into three different classes characterized, respectively, as "strong and efficient," "strong and inefficient," and "balanced." For weakly coupled multicyclic machines, efficiency at maximum power has lost any universality even in the linear response regime. © 2011 The American Physical Society. Source

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