科研之友
微信
新浪微博
Facebook
分享链接
摘要
A software program has been developed on the MATLAB platform, which is useful for studying the nucleation kinetics of crystals grown from solutions. Nucleation parameters such as interfacial energy (sigma), metastable zone width (Delta T-max), volume free energy (Delta G(v)), critical energy barrier for nucleation (Delta G*), radius of the critical nucleus (r*) and nucleation rate (J) of the crystals are determined from classical nucleation theory. The Metastable Zone Width (MZW) of the crystals is explored by using the relation based on solubility and enthalpy of nucleation. A new polynomial equation has been generated by this software program, and the results are checked with the experimental data of crystal growth/formation. Nucleation temperature as a function of supersaturation ratio was successfully evaluated using MZW. The equation relating to the nucleation kinetics and MZW can easily be solved with the help of a newly designed software program in the MATLAB platform. In addition, a program has been developed that highlights changes in nucleation parameters when the supersaturation ratio is changed. A plot of temperature vs energy barrier, nucleation rate and interfacial energy is also drawn. Program summary Program title: Nucleation Catalogue identifier: AERG_v1_0 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AERG_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 6305 No. of bytes in distributed program, including test data, etc.: 616560 Distribution format: tar.gz Programming language: MATLAB (MathWorks Inc.) version R2013a. Statistics Toolbox and Curve Fitting Toolbox required Computer: Any computer running MATLAB (MathWorks Inc.) Operating system: Tested on Windows XP, but generally it would work on any computer running MATLAB (MathWorks Inc.) RAM: 32 MB Classification: 8 Nature of problem: In crystal growth, the knowledge of nucleation thermodynamical parameters like interfacial energy, metastable zone width (supercooling temperature), volume free energy, critical energy barrier for nucleation, radius of critical nucleus and nucleation rates is essential for the growth of good quality bulk single crystals. In these parameters, metastable zone width determination is very useful for growth. Also some curve fitting tool is needed to obtain more information about nucleation kinetics. Solution method: In this program, an attempt has been made to calculate nucleation parameters theoretically to understand the role of these nucleation thermodynamical parameters for crystallization. A linear fit is done to calculate enthalpy of solution and polynomial fitting is used to derive the saturation concentration equation. Metastable zone width was calculated by the enthalpy-supersaturation relation. Supersaturation control is a decisive parameter for optimizing growth conditions during crystallization processes. The effects of metastable zone width and nucleation rate of crystals caused by changes in different supersaturation ratios were analyzed. Running time: Interactive and instantaneous.
- 出版日期2014-2
