| 研究概要 |
The aim of our project is to elucidate with the X-ray Free Electron laser (XFEL) real-time dynamic behavior from porous coordination polymers (PCP) under stimuli (gas, light).
From FY 2012, we had three beam times (Nov 2012, Feb 2013, Nov 2013). In these beam times, we have gradually improved our sample cells and detector. From the first beam time, the sample cell was an open holder and we could only have a 2-theta 10 degree range for our detector. Now we could do diffraction in capillaries with a MPCCD detector possessing 2-theta 40 degree range.
In our first beam time in Nov 2012, we measured static samples of 1, [Zn(ip)(bpy)]; 2, [Cu(ip)(H2O)]; 3, [Zn(5-NO2-ip)(dpe)] (bpy= bipyridine, H2ip= isophtalic acid, dpe= 1,2-di(4-pyridyl)ethylene). Note the results are obtained for accumulation of 1000 shots.
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| 現在までの達成度 (区分) |
現在までの達成度 (区分)
2: おおむね順調に進展している
理由
Recently, we attempted to perform [2+2] photodimerization with XFEL laser at 260 nm on 4, [Zn(isopthalic)(bpy)], which we have previously published on. Since the sample cells were sealed capillaries, we repeated the same irradiation under an atmosphere of CO2. However we did not observe any significant changes in the diffraction pattern.
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| 今後の研究の推進方策 |
For our next beam time, we will attempt to do cis-trans isomerism of azo-benzene in a soft porous coordination polymer (PCP), Zn-JAST-1 or [Zn(bdc)(DABCO)] (H2BDC= terephthalic acid, DABCO= 1,4-diazabicyclo[2.2.2]octane). On irradiation, the XRD pattern changes from tetragonal to monoclinic. With the pico-second time scale of the phase change of azobenzene and the time resolution of the XFEL laser at pico-seconds, we intend to use the XFEL to see the transformation of the PCP lattice with time with the help of pump probe reactions.
There are also plans to shift the gas adsorption system from Spring 8 to SACLA in the near future to enable us to study the dynamic breathing behavior of PCP under gas stimuli.
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