実験報告書様式（一般利用課題・成果公開利用）

MLF Experimental Report

提出日 Date of Report

課題番号 Project No.

装置責任者 Name of responsible person

2009B0049

Ichiro Tanaka

実験課題名 Title of experiment

装置名 Name of Instrument/（BL No.）

Disordered crystal structure and intrinsic temperature factors ofiBIX at BL-03

an electride by TOF neutron diffraction

実施日 Date of Experiment

実験責任者名 Name of principal investigator

2010/1/20 - 1/26

Kiyoaki Tanaka
所属 Affiliation
Nagoya institute of Technology （ present address ： Nagoya
Industrial Science research institute）
試料、実験方法、利用の結果得られた主なデータ、考察、結論等を、記述して下さい。（適宜、図表添付のこと）
Please report your samples, experimental method and results, discussion and conclusions. Please add figures andtables for better explanation.
1. 試料 Name of sample(s) and chemical formula, or compositions including physical form.
Inorganic Electrides
a. Ca12Al14O32.529(14)(C12A7:e, electric conductivity a room temperature ７00S/cmm)b. Ca12Al14O32.(C12A7:2e, electric conductivity at room temperature 1500S/cmm)
Both crystals were shaped into cubes with an edge of 2mm and were used for the experiment with the neutron
TOF diffraction experiment.

2. 実験方法及び結果 （実験がうまくいかなかった場合、その理由を記述してください。）
Experimental method and results.

If you failed to conduct experiment as planned, please describe reasons.

TOF neutron diffraction experiment was done and the intensity data measured on two dimensional detector
were indexed and were converged to structure factors successfully. The analysis of the data will soon start
after the publication of the results on C12A7.
The experiment was done as a part of our project of investigating the electron density distribution of theelectrons left inside of the cages of Ca12Al14O32+x(C12A7:e), which is called as 'free' electrons here. Since thecrystal structure of C12A7:e is ｃlosely related to that of C12A7 and tiny distortion of the crystal structure
due to O ions included perfectly randomly in two cages among the 12 cages in the unit cell, more accurate andhigher resolution single crystal diffraction experiments are necessary. Therefore, the following three kinds ofexperiments using the facilities of neutron diffraction at J-PARC and LANCE, and of X-ray diffraction at PF
have been done in our investigation on the inorganic electride:.
1. The X-ray diffraction experiment at PF on C12A7, C12A7:e and C12A7:2e was already finished.
2. The TOF neutron diffraction experiment at LANCE on C12A7 was finished.
3. The TOF neutron experiment at J-PARC on C12A7:e and C12A7:2e is reported here.
12. 実験方法及び結果（つづき） Experimental method and results (continued)
The results on the X-ray crystal structure of C12A7 are now being prepared for publication. The X-ray
study of C12A7 revealed the detailed local deformed structure due to the O ions included in a cage and will bea firm base for further investigation on the inorganic electride. The neutron experiment at LANCE with higher
resolution than the X-ray experiment will reveal more detailed splitting of atomic positions due to the included
O ion. Based on these studies the diffraction data measured at J-PARC will be analysed and the detailed
splitting of atoms of a cage including 'free' electrons left after the removal of O ion will be made clear. The
electron density distribution measured by X-ray diffraction is the sum of those of the electrons in the cageand those around the electronic orbitals of ions. Therefore, the electron density of the 'free' electrons, whichis expected to be very small, can be made clear only after analysing perfectly the splitting of ions.

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