[3/13] The 3rd “AIMR Seminar”
Speaker
Prof. Ryoko Tomiyasu (Institute of Mathematics for Industry, Kyushu University)
Title
Applications of lattice-basis reduction theory to crystal structure analysis
Date
March 13 (Wed), 2024, 16:00–17:00 on Japan Time
Venue
Seminar Room, 2nd floor, AIMR Main Building
Abstract
This talk concerns the mathematics used for the powder ab-initio indexing software CONOGRAPH we released 10 years ago, which improves the success rate by 20-40% compared to the classical software ITO/TREOR/DICVOL in computation time similar to them. To date, CONOGRAPH's ideas have been applied to ab-initio indexing of electron backscattered diffraction and transmission electron microscopy (TEM) images.
However, it is not widely recognized, even among software users, how rigorous mathematics was utilized for the improvement. In particular, the lattice-basis reduction theory was useful for developing new and efficient methods to solve the following subproblems.
- (a) ab-initio indexing algorithms using a graph structure called Conway's topograph,
- (b) error-stable Bravais lattice determination,
- (c) unit-cell identification to avoid multiple outputs of very close unit-cells represented by the Niggli-reduced parameters.
In crystallography, the Niggli-Eisenstein reduction has been used to uniquely parametrize crystal lattices. As its derivation, (c) has been discussed mainly outside of mathematics because of its cross-disciplinary nature (algebra, geometry, and statistics).
In more recent years, for the purpose of materials design, the use of rigorous mathematics is discussed to obtain efficient methods for identification and parametrization (so called, moduli space in mathematics) of crystal structures and lattices. I will explain how the lattice-basis reduction (such as Minkowski, Selling, Voronoi, Venkov, and Ryskov C-type etc.) can be used for all of the mentioned problems.
AIMR Seminars and Tea Time
We hold AIMR Seminars and Friday Tea Time as part of the initiative to promote fusion research.
Seminars are presented by AIMR researchers and visiting scientists who provide a wide range of hot topics from materials science to mathematics. The aims of the AIMR Seminar are to build up mutual understanding, communication, and discussions of each other’s research fields.
Weekly held Friday Tea Time is where AIMR researchers and staff members can relax and talk freely while drinking coffee. Expectations of stimulating conversation may arise among the researchers and leading to new research.
From 2024, active fusion research through synergistic effects from AIMR Seminars and Friday Tea Time will be promoted.
Past AIMR Seminar
| 2nd | Jan. 26, 2024 | Prof. Michael I. Ojovan (Imperial College London, U.K.) |
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| 1st | Jan. 12, 2024 | Dr. William Chuck Witt (University of Cambridge, U.K.) |
About Tea Time Talk
As part of an event during Friday Tea Time, AIMR has been hosting lectures by famed researchers and the archives up to 2023 are listed below:
| 43rd | July 21, 2023 | Prof. Feral Temelli (University of Alberta, Canada) |
|---|---|---|
| 42nd | June 30, 2023 | Dr. Douglas Brumley (The University of Melbourne, Australia) |
| 41st | Mar. 28, 2023 | Prof. Motomu Tanaka (Physical Chemistry of Biosystems, Institute of Physical Chemistry, Heidelberg University, Germany) |
| 40th | Nov. 10, 2022 | Prof. Masahiro Yoshimura (National Cheng Kung University, Taiwan) |
| 39th | June 17, 2022 | Prof. Rana Mohtadi (Toyota Research Institute of North America) |
| 38th | June 17, 2022 | Prof. Michael Hirscher (Max-Planck-Institute for Intelligent Systems, Germany) |
| 37th | June 3, 2022 | Prof. Reiko Oda (French National Centre for Scientific Research) |
| 36th | May 28, 2021 | Prof. Magda Titirici (Imperial College London, U.K.) |
| 35th | Mar. 26, 2021 | Prof. Yaroslav Blanter (Kavli Institute of Nanoscience, Delft University of Technology) |
| 34th | Oct. 23, 2020 | Dr. Kazuhito Tsukagoshi (PI:WPI-MANA, NIMS & AIMR) |
| 33rd | July 17, 2020 | Prof. Kaoru Tamada (IMCE, Kyushu University & AIMR) |
| 32nd | Jan. 17, 2020 | Prof. Miho Yamauchi (I2CNER / Kyushu University & AIMR) |
| 31st | Jan. 17, 2020 | Prof. Mickaël Lallart (INSA Lyon, Université de Lyon) |
| 30th | Oct. 25, 2019 | Assoc. Prof. Frédéric Gillot (Department of Solid Mechanics, Mechanical Eng. and Civil Eng., École Centrale de Lyon) |
| 29th | July 12, 2019 | Prof. Qian Niu (Department of Physics, The University of Texas at Austin) |
| 28th | May 17, 2019 | Prof. Damien Fabrègue (INSA Lyon, France / ELyT MaX Lab at Tohoku University) |
| 27th | Dec. 14, 2018 | Prof. Yukitoshi Motome (Department of Applied Physics, The University of Tokyo, Japan) |
| 26th | July 13, 2018 | Dr. Shimpei Ono (Central Research Institute of Electric Power Industry, Japan) |
| 25th | May 11, 2018 | Dr. Pierre-Antoine Geslin (Mateis lab, INSA Lyon/CNRS / ELyTMaX Lab at Tohoku University / Institute for Materials Research, Tohoku University) |
| 24th | Apr. 27, 2018 | Prof. Masaru Tsukada (AIMR, Tohoku University) |
| 23rd | Dec. 8, 2017 | Prof. Jean-Yves Cavaillé (INSA Lyon, France / ELyT MaX Lab at Tohoku University) |
| 22nd | July 28, 2017 | Prof. Nicolas Mary (INSA Lyon, France / ELyT MaX Lab at Tohoku University) |
| 21st | July 21, 2017 | Prof. Gael Sebald (INSA Lyon, France / ELyT MaX at Tohoku University) |
| 20th | July 7, 2017 | Prof. Arun Bansil (Northeastern University) |
| 19th | June 30, 2017 | Dr. Takeshi Nakanishi (AIST-Tohoku U Mathematics for Advanced Materials Open Innovation Laboratory (MathAM-OIL)) |
| 18th | June 23, 2017 | Prof. Denis Arčon (Jožef Stefan Institute, Slovenia) |
| 17th | Apr. 28, 2017 | Prof. Ayumi Hirano (AIMR, Tohoku University) |
| 16th | Nov. 29, 2016 | Dr. David Guy Austing (National Research Council Canada, Canada) |
| 15th | Sept. 30, 2016 | Prof. C. Suryanarayana (University of Central Florida, U.S.A.) |
| 14th | June 17, 2016 | Prof. Tomoteru Fukumura (AIMR, Tohoku University) |
| 13th | May 13, 2016 | Prof. Jean-Yves Cavaillé (ELyT MaX (Joint Lab at Tohoku University), University of Lyon, France) |
| 12th | June 26, 2015 | Dr. B. Muralidharan (Indian Institute of Technology Bombay, India) |
| 11th | June 27, 2014 | Prof. Michael B. Santos (The University of Oklahoma, U.S.A.) |
| 10th | Nov. 19, 2013 | Dr. Pawel Hawrylak (National Research Council Canada, Canada) |
| 9th | Oct. 1, 2013 | Dr. Yuan T. Lee (Nobel laureate in Chemistry, Academia Sinica of Taiwan) |
| 8th | June 28, 2013 | Dr. Bjorn Mysen (Geophysical Laboratory, Carnegie Institution for Science, U.S.A.) |
| 7th | Apr. 12, 2013 | Prof. Yiming Li (National Chiao Tung University, Taiwan) |
| 6th | Jan. 18, 2013 | Prof. Tomasz Dietl (Polish Academy of Sciences, Poland) |
| 5th | Aug. 31, 2012 | Prof. John H. Perepezko (University of Wisconsin-Madison, U.S.A.) |
| 4th | Aug. 17,2012 | Prof. Alain Reza Yavari (Grenoble Institute of Technology, France) |
| 3rd | Aug. 10, 2012 | Prof. Alan Lindsay Greer (University of Cambridge, U.K.) |
| 2nd | July 6, 2012 | Prof. Winfried Teizer (Texas A&M University, U.S.A.) |
| 1st | May 25, 2012 | Prof. Thomas P. Russell (The University of Massachusetts Amherst, U.S.A.) |
Contact
Kazuto Akagi
Deputy Director, Research Support Division, AIMR
| E-mail: | kazuto.akagi.b5@tohoku.ac.jp |
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