Industrial (Define the properties, performance criteria, and molecular systems of interest and indicate the required level of accuracy and the appropriate temperatures, pressures, and process conditions for each of these properties.)
In order to help focus the efforts of modelers, it makes sense to consider physical properties that are important to the chemical industry. Specifically, these are product properties that influence process design and scale-up. For example, what are the key materials, intermediates, or general chemical classes in the chemical industry? Where are the holes in physical property data for key compounds or classes of compounds? Where are the experimentally challenging regimes of T, P, density? Can the pilot plant be abandoned? The list should be complemented by a determination of where molecular simulation methods might offer an advantage over current methods.
We all agree on the potential impact areas for molecular simulation methodology, i.e. better experiments, insights, etc. At the same time, we also all agree that these tools are not yet fully implemented in any industry. Why? What are the current and future barriers to be overcome? How do we envision this methodology fitting in the future? Where do we want this to be in five or ten years?
Force Fields (Define the current state of the art with respect to reliability and accuracy and identify future challenges.)
Methods (Define the current state of the art for evaluating the properties of interest and identify the barriers to progress.)
Programmatic (Make recommendations and plan future events and activities)
The Workshop on Predicting the Thermophysical Properties of Fluids by Molecular Simulation will establish a series of tutorials on aspects of molecular simulation geared mainly to users or prospective users of these methods, but also including subjects of interest to expert practitioners in this field. These tutorials will be held in conjunction with _______ meetings. Some prospective topics are listed below.
Introduction to Molecular Modeling
Force Fields for Molecular Systems
Predicting Thermophysical Properties from Electronic Structure Calculations and Solvation Models
Non-Equilibrium Molecular Dynamics
Simulating Phase Equilbria
Biased Monte Carlo Moves
Thermostats, Barostats and Equilibration in Molecular Modeling
Estimating Uncertainties in Molecular Simulations
The proceedings of the Workshop on Predicting the Thermophysical Properties of Fluids by Molecular Simulation will be prepared for publication in an archival journal. To facilitate publication, the presentations and discussions at the Workshop will be recorded and reporters will be assigned to each session. However, to ensure the flow of candid discussion, no statement of fact or opinion made by a particular speaker will be published in the proceedings unless the speaker has had an opportunity to review, revise, or retract this statement. The chair of the publication committee will be _______.
In order to facilitate communication of the results and activities of the Workshop on Predicting the Thermophysical Properties of Fluids by Molecular Simulation, a web site will be established. The initial web site will be created by _______ and the organizing committee at NIST, but a web site committee will be established at the Workshop in order to maintain and update the site.
The Workshop on Predicting the Thermophysical Properties of Fluids by Molecular Simulation will provide the following current recommendations for the calculation of properties using molecular simulation. These recommendations are subject to revision as additional information and comments are gathered. They are intended to provide guidance to industrial users of molecular simulation tools, and are not intended to discourage innovation or attempts to implement and validate alternative methods.
The Workshop recommends that all publications reporting results based on molecular simulation provide estimates of the uncertainties of the results. The following guidelines for the reporting of uncertainties in simulation studies should be used: _________
For quantum chemistry calculations, the following recommendations are provided: _________
For calculations of phase equilbrium in mixtures, the Gibbs ensemble method is recommended_______
The Workshop recommends that all publications reporting results based on molecular simulations provide the numerical answers of their results. Limiting results solely to figures is not satisfactory. The numerical results can be published as Supplementary Information (if the scientific journal allows for this) or should be published on the home-page of the corresponding author. The workshop recommends that all publications reporting results based on molecular simulation shall provide full details of force fields or provide the appropriate references to the open literature.
The rules of the competition are as follows:
|(a)||Each contestant can consider any or all of the posed problems.|
|(b)||Full details about the competition will be posted on the Workshop web site on or about ________; upon e-mail request to the competition chair (_______), notification will be given when the information is available.|
|(c)||The simulation methods and force field should be adequately documented so that, upon reasonable effort, others can reproduce identical results. References to previously published documentation, available in the open literature, may be appropriate.|
|(d)||Because this competition is considered a test of predictive methods, only data that have been provided within the context of the competition can be used in the development or optimization of any parameters used within the simulation.|
|(e)||If a contestant considers that some additional and available information would be appropriate in the solution of the problem, such information should be sent to the competition chair. If the competition committee feels that this information is useful, it will be posted on the Workshop web site so that it will be available to all contestants.|
|(f)||Entries will be due 6 months after the announcement of the contest.|
|(g)||The evaluations will be completed within 3 months of entry deadline. These evaluations will be based on available experimental data, including new data obtained as part of this competition. These evaluations will also attempt to ensure that a prospective winning entry has sufficient documentation (rule c) and that no disallowable data were used in any part of the parameterization or optimization (rule d).|
|(h)||Prizes will be awarded as follows: _____; a manuscript for featured publication will be solicited from the contributor of each winning entry.|
|(i)||The molecular simulation community and the prospective user community can learn from an assortment of different techniques. For this reason, we encourage entries, such as those based on novel techniques, general purpose force fields, etc.|
It is anticipated that this competition will be an annual program, with the purpose of driving improvements in the practice of molecular modeling, formalizing methods for the evaluation and validation of simulation results with experimental data, and ensuring relevance of simulation activities to industrial requirements.
For the first competition, the following problems are being considered:
|(i)||Compressibility factor for _________ (CAS # ) at T = 280 K, P = 0.1 MPa and T = 350 K, P = 5 MPa.|
|(ii)||Solubility limit of ___________ in water at T = 310 K, P = 0.1 MPa.|
|(iii)||Viscosity (Newtonian) of a polyolester lubricant (_____) at T = 280 K, P = 0.1 MPa and T = 350 K, P = 0.1 MPa.|
|(iv)||Location of an azeotrope in a binary mixture of _____ + _____ at T = ____.|
|(v)||Isobaric heat capacity of ______|
|(vi)||Thermal conductivity of ______|
|(vii)||Phase diagram of a 4-component hydrocarbon mixture (_____) at fixed T = 250 K and P < 20 MPa.|
In order to demonstrate the robustness and range of applicability of their approach, competitors will be encouraged to perform a sensitivity analysis to identify key force field parameters, to provide values for additional properties, and to evaluate the same properties on structurally related molecules.
The Workshop on Predicting the Thermophysical Properties of Fluids by Molecular Simulation will initiate efforts to establish a consortium to help advance the state of molecular simulation. The main areas of focus will be force field development and validation, algorithmic development, and assisting with the conduct of the annual competition for molecular simulation.
Upon expressions of interest from at least 10 companies with prospective financial commitments of $10 000 apiece, the charter for the consortium will be written and balloted. It is expected that expenditures of funds from the consortium will be decided by a majority vote of members, with contracts being implemented for specific projects of general interest to the community.
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