Genetic algorithms (GAs) represent a family of powerful global-search methods applicable to solving high-complexity optimisation tasks in science, technology and everyday life. The global-optimisation strategies based on the genetic approach mimic the evolution of living organisms. Applications in materials science, physics, chemistry, crystallography, technology, industry, medicine, economy, communication can be found in literature. In crystallography and related fields, the GAs are used e.g. for molecular design, for structure prediction, and for solving structures. Moreover, they constitute an important tool for image analysis, e.g. in medicine, and can be used for analysis of various kinds of data collected at 2D detectors.
Mutation is one of operators employed in GAs. Typically, it consists of flipping a single bit with a small probability (mutation rate, M). Using this operator ascertains that whole parameter space is searched. The value of M is either fixed at the level ~1% - ~5%, or is adjusted during calculations. In the present study, the role of M value for the success and for the calculation speed is studied on a test example of powder-diffraction data of an orthorhombic crystal. The convergence of the algorithm was determined for 20000, 30000, 60000 and 100000 function calls (during ~200-400 generations) on the basis of multiple test calculations. The probability of finding the global optimum is found to be strongly influenced by the M value. When M equals 1.8%, the chance for successful finding the global optimum is 0.2, only (in remaining cases the algorithm converged to some local minimum). The process of reaching the global minimum is fast then (stopping criterion of 20000 calls is sufficient). For the M value being twice as high (3.7), the chance for success increases to 0.8, but at expense of calculation time (stopping criterion of 100000 calls). The study demonstrates how sensitive is the algorithm to the value of the mutation rate.

• Legal notice:
  

  Copyright (c) Pielaszek Research, all rights reserved.
  The above materials, including auxiliary resources, are subject to Publisher's copyright and the Author(s) intellectual rights. Without limiting Author(s) rights under respective Copyright Transfer Agreement, no part of the above documents may be reproduced without the express written permission of Pielaszek Research, the Publisher. Express permission from the Author(s) is required to use the above materials for academic purposes, such as lectures or scientific presentations.
  In every case, proper references including Author(s) name(s) and URL of this webpage: https://science24.com/paper/2375 must be provided.

1. Defect distribution along needle-shaped PrVO₄ single crystals grown by the slow-cooling method
2. The influence of growth atmosphere on the self-selection of the grains during ZnO crystal growth
3. New Ca₁₀Li(VO₄)₇ laser host: growth and properties
4. Up-conversion and down-conversion processes observed in Er³⁺, Yb³⁺ and Mn²⁺ doped ZnAl₂O₄ nanoparticles
5. Synthesis and properties of up-converted NaYF₄: Er, Yb nanoparticles for biomedical applications
6. Structural, morphological and optical properties of ZnAl₂O₄ nanoparticles co-doped with Er³⁺and Yb³⁺ prepared by combustion aerosol synthesis.
7. Synthesis and properties of NaYF₄: Er, Yb, Gd nanoparticles with and without SiO₂ coating for biomedical applications.
8. Designing biosensors based on semiconductor nanoparticles for an early detection of neurodegenerative diseases.
9. High-pressure diffraction study of structural and elastic properties of zircon-type and scheelite-type RVO₄ (R = Nd, Eu)
10. Elastic properties of dysprosium orthovanadate: An in-situ powder-diffraction study
11. Thermal expansion of Si₃N₄ and Ge₃N₄
12. ZnO and core/shell ZnO/ZnS nanofibers: Characterization and applications
13. Zinc oxide grown by Atomic Layer Deposition - a material for novel 3D electronics
14. Thin films of ZnS and ZnSe by Atomic Layer Deposition for light sensor applications
15. Effects related to deposition temperature of ZnCoO films grown by Atomic Layer Deposition – uniformity of Co distribution, structural, electric and magnetic properties
16. Pressure dependence of lattice parameter of Gadolinium Gallium Garnet crystals
17. Lattice parameters of hard materials in the low-temperature range
18. Lattice parameters of a wurtzite-type (Zn,Mg)Se crystal as a function of temperature
19. Rietveld refinement for Li₂Si₂O₅ doped with vanadium
20. High-pressure diffraction study of α and β Ge₃N₄
21. Effect of annealing on the structure and microstructure of Pr doped ZrO₂-Y₂O₃ nanocrystals
22. ZnO thin films for organic/inorganic heterojunctions
23. Optimisation of parameters of a dynamic penalty function for a test example of powder pattern indexing
24. Wide band-gap II-VI semiconductors for optoelectronic applications
25. Low temperature ZnMnO by ALD
26. Substrate effect on the ground state of the magnetic order in NSMO/YBCO superlattices
27. Method of Manganese co-doping of LT ZnO films
28. Ferromagnetism in ZnO:Mn thin films deposited by PEMOCVD
29. Structure properties of bulk ZnO crystals
30. Magnetic anisotropy and structural properties of ferromagnet/MgO/ferromagnet system
31. Rietveld refinement for polycrystalline indium nitride
32. LATTICE PARAMETERS OF INDIUM NITRIDE IN THE 22-310 K TEMPERATURE RANGE
33. Promising high quality short period Fe/Fe-N multilayers deposited by the sputtering
34. Structural and Magnetic Properties of Cr/Gd Multilayers Deposited on Sapphire and MgO Substrates
35. X-ray diffraction studies of thermal-expansion with the use of 1D detectors installed at synchrotron beamlines
36. Rietveld refinement of powder diffraction data collected with a laboratory diffractometer equipped with a linear X-ray detector
37. Phase relationships in annealed Cu-Al-O layers
38. Growth and characterization of thin films of ZnO by Atomic Layer Epitaxy
39. Area detector as a tool to study properties of the magnetic multilayers by the neutron scattering
40. Influence of hydrogen adsorption on magnetic properties of Fe films and multilayers
41. Transmission electron microscopy and X-ray diffraction study of α'-Al₂ CO crystals
42. Diamond as X-ray Wavelength Standard for Thermal-Expansion Studies Using Synchrotron Sources
43. X-Ray Study of Lattice Parameters of GaN in a Broad Temperature Range