The Experts below are selected from a list of 30 Experts worldwide ranked by ideXlab platform
Dung Di Caprio - One of the best experts on this subject based on the ideXlab platform.
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Field theoretical approach to the liquid state. Elements of comprehension of the role of the Ideal Entropy
Journal of Molecular Liquids, 2007Co-Authors: Dung Di Caprio, J. StafiejAbstract:In a series of papers we have introduced a field theoretical approach to describe the liquid state. The formalism introduces a simple Hamiltonian which includes the Ideal gas free energy and the standard interaction potential between particles coupling the fields. In this paper, we discuss the role and the importance of the Ideal term in this formalism. We compare our approach to the standard liquid state theory and another approach based on a field description, the density functional theory where an identical functional appears. The comparison shows that field theory sheds new light on the role of the Ideal Entropy an aspect which is traditionally discarded in favor of a viewpoint focusing on the interaction potential.
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Field theoretical description of the liquid state. Exact relations. The role of the Ideal Entropy revisited
Molecular Physics, 2006Co-Authors: Dung Di Caprio, Jean-pierre Badiali, Janusz StafiejAbstract:In a series of papers, we have used a field theoretical description of the liquid state for a study of ionic systems. The formalism constructed is based on a simple Hamiltonian including the interaction potential and the Ideal Entropy. We discuss and analyse the Hamiltonian by detailing the role of its different contributions and its physical content. We show that the simple Hamiltonian based on particle densities as the fields also reproduces exactly the usual liquid state theory formulated in a discrete particle description rather than continuous fields. In this perspective, the formalism is discussed in view of a well-known exact and fundamental relation of the liquid state theory: the contact theorem. We demonstrate the validity of this theorem within the field theoretical framework. We find that the specific form of the Hamiltonian, in particular of the Ideal Entropy functional, is essential. The analysis of this term shows that it introduces the basic principle of uncertainty and the principle of the indiscernibility of quantum physics which exists for particles in a way suited for a description in terms of fields. This discussion is illustrated in the case of an ionic solution at an interface.
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Density field theory for a fluid interacting with the Yukawa potential. Role of the Ideal Entropy
Molecular Physics, 2003Co-Authors: Dung Di Caprio, Janusz Stafiej, Jean-pierre BadialiAbstract:We present a field theory to describe liquids where the field represents the density. In terms of this field, the Hamiltonian contains the Ideal Entropy and the interaction between the density fields. The approach is illustrated with the Yukawa interaction and presented in the grand canonical ensemble formalism. In this framework, first, we derive a relation specific to the field theory. This relation is equivalent to the ‘equation of motion’ in field theory for interacting quantum particles. Then, focusing on the effect of the fluctuations, we calculate thermodynamic quantities beyond the mean field. The pressure, the density and the compressibility at a given chemical potential in the quadratic approximation and beyond are given. The aim of this paper is to illustrate the importance and the role of the Ideal Entropy in this type of approach. The density and the compressibility at a given chemical potential are calculated perturbatively in various ways. Whether from their field theoretical definition, or...
J. Stafiej - One of the best experts on this subject based on the ideXlab platform.
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Field theoretical approach to the liquid state. Elements of comprehension of the role of the Ideal Entropy
Journal of Molecular Liquids, 2007Co-Authors: Dung Di Caprio, J. StafiejAbstract:In a series of papers we have introduced a field theoretical approach to describe the liquid state. The formalism introduces a simple Hamiltonian which includes the Ideal gas free energy and the standard interaction potential between particles coupling the fields. In this paper, we discuss the role and the importance of the Ideal term in this formalism. We compare our approach to the standard liquid state theory and another approach based on a field description, the density functional theory where an identical functional appears. The comparison shows that field theory sheds new light on the role of the Ideal Entropy an aspect which is traditionally discarded in favor of a viewpoint focusing on the interaction potential.
Janusz Stafiej - One of the best experts on this subject based on the ideXlab platform.
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Field theoretical description of the liquid state. Exact relations. The role of the Ideal Entropy revisited
Molecular Physics, 2006Co-Authors: Dung Di Caprio, Jean-pierre Badiali, Janusz StafiejAbstract:In a series of papers, we have used a field theoretical description of the liquid state for a study of ionic systems. The formalism constructed is based on a simple Hamiltonian including the interaction potential and the Ideal Entropy. We discuss and analyse the Hamiltonian by detailing the role of its different contributions and its physical content. We show that the simple Hamiltonian based on particle densities as the fields also reproduces exactly the usual liquid state theory formulated in a discrete particle description rather than continuous fields. In this perspective, the formalism is discussed in view of a well-known exact and fundamental relation of the liquid state theory: the contact theorem. We demonstrate the validity of this theorem within the field theoretical framework. We find that the specific form of the Hamiltonian, in particular of the Ideal Entropy functional, is essential. The analysis of this term shows that it introduces the basic principle of uncertainty and the principle of the indiscernibility of quantum physics which exists for particles in a way suited for a description in terms of fields. This discussion is illustrated in the case of an ionic solution at an interface.
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Density field theory for a fluid interacting with the Yukawa potential. Role of the Ideal Entropy
Molecular Physics, 2003Co-Authors: Dung Di Caprio, Janusz Stafiej, Jean-pierre BadialiAbstract:We present a field theory to describe liquids where the field represents the density. In terms of this field, the Hamiltonian contains the Ideal Entropy and the interaction between the density fields. The approach is illustrated with the Yukawa interaction and presented in the grand canonical ensemble formalism. In this framework, first, we derive a relation specific to the field theory. This relation is equivalent to the ‘equation of motion’ in field theory for interacting quantum particles. Then, focusing on the effect of the fluctuations, we calculate thermodynamic quantities beyond the mean field. The pressure, the density and the compressibility at a given chemical potential in the quadratic approximation and beyond are given. The aim of this paper is to illustrate the importance and the role of the Ideal Entropy in this type of approach. The density and the compressibility at a given chemical potential are calculated perturbatively in various ways. Whether from their field theoretical definition, or...
Martin Kroger - One of the best experts on this subject based on the ideXlab platform.
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Ideal contribution to the macroscopic quasiequilibrium Entropy of anisotropic fluids
Physical Review E, 2011Co-Authors: Patrick Ilg, Markus Hutter, Martin KrogerAbstract:The Landau-de Gennes free energy plays a central role in the macroscopic theory of anisotropic fluids. Here, the Ideal, entropic contribution to this free energy-that is always present in these systems, irrespectively of the detailed form of interactions or applied fields-is derived within the quasiequilibrium ensemble and successfully tested. An explicit and compact form of the macroscopic, Ideal Entropy is derived. This Entropy is nonpolynomial in the order parameter, diverging logarithmically near the fully oriented state and therefore restricting the order parameter to physical admissible values. As an application, it is shown that the isotropic-nematic transition within the Maier-Saupe model is described in a simple and very accurate manner.
Jean-pierre Badiali - One of the best experts on this subject based on the ideXlab platform.
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Field theoretical description of the liquid state. Exact relations. The role of the Ideal Entropy revisited
Molecular Physics, 2006Co-Authors: Dung Di Caprio, Jean-pierre Badiali, Janusz StafiejAbstract:In a series of papers, we have used a field theoretical description of the liquid state for a study of ionic systems. The formalism constructed is based on a simple Hamiltonian including the interaction potential and the Ideal Entropy. We discuss and analyse the Hamiltonian by detailing the role of its different contributions and its physical content. We show that the simple Hamiltonian based on particle densities as the fields also reproduces exactly the usual liquid state theory formulated in a discrete particle description rather than continuous fields. In this perspective, the formalism is discussed in view of a well-known exact and fundamental relation of the liquid state theory: the contact theorem. We demonstrate the validity of this theorem within the field theoretical framework. We find that the specific form of the Hamiltonian, in particular of the Ideal Entropy functional, is essential. The analysis of this term shows that it introduces the basic principle of uncertainty and the principle of the indiscernibility of quantum physics which exists for particles in a way suited for a description in terms of fields. This discussion is illustrated in the case of an ionic solution at an interface.
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Density field theory for a fluid interacting with the Yukawa potential. Role of the Ideal Entropy
Molecular Physics, 2003Co-Authors: Dung Di Caprio, Janusz Stafiej, Jean-pierre BadialiAbstract:We present a field theory to describe liquids where the field represents the density. In terms of this field, the Hamiltonian contains the Ideal Entropy and the interaction between the density fields. The approach is illustrated with the Yukawa interaction and presented in the grand canonical ensemble formalism. In this framework, first, we derive a relation specific to the field theory. This relation is equivalent to the ‘equation of motion’ in field theory for interacting quantum particles. Then, focusing on the effect of the fluctuations, we calculate thermodynamic quantities beyond the mean field. The pressure, the density and the compressibility at a given chemical potential in the quadratic approximation and beyond are given. The aim of this paper is to illustrate the importance and the role of the Ideal Entropy in this type of approach. The density and the compressibility at a given chemical potential are calculated perturbatively in various ways. Whether from their field theoretical definition, or...
