2022 Fiscal Year Final Research Report

Identification of chirarity and absolute configuration of molecules by using atom probe

Research Project

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Project/Area Number	19K05188
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Review Section	Basic Section 28010:Nanometer-scale chemistry-related
Research Institution	Kanazawa Institute of Technology
Principal Investigator	Taniguchi Masahiro 金沢工業大学, バイオ・化学部, 教授 (30250418)
Co-Investigator(Kenkyū-buntansha)	小野慎金沢工業大学, バイオ・化学部, 教授 (10214181)
Project Period (FY)	2019-04-01 – 2023-03-31
Keywords	atom probe / field ion microscopy / surface analysis / chiral discrimination / mass spectroscopy / metal chelate
Outline of Final Research Achievements	The combined instrument of field ion microscope and atom probe mass analyzer (FIM-AP) enables the atomic scale structural observation and the identification by mass analysis in an atom-by-atom manner. In this research, the energy filtering by a toroidal sector lens and the deflection/shifting of the FIM image was installed to the conventional FIM-AP instrument to enable the synchronous operation of FIM and AP in an atom-by-atom sequence. The new system showed the detection efficiency of ca. 1/3 against surface atoms desorbed in a sequence of field evaporation of tungsten. The candidate species were searched for the determination of the absolute chirality of an isolated molecule by mass spectrometry. The triply or doubly chelated metal chelate complexes of phenanthroline ligand were successfully AP analyzed by using carbon fiber as substrate (filed emitter). The mass spectra showed the dissociation of bidentate ligands was dominant and the desorbed species were easily identified.
Free Research Field	Surface Chemistry
Academic Significance and Societal Importance of the Research Achievements	本研究は表面での実空間、原子スケールでの構造情報(電界イオン顕微鏡)とイオン一個ずつの検出を行なう質量分析法(アトムプローブ)による化学種同定によって、分子不斉の決定を表面で行おうとするものである。この方法は分子スケール局所領域での検出能を必要とするために、イオンの検出効率を最大限かつ個数レベルで明確にする必要がある。本研究で改良したFIM-APによって、脱離したイオンを実際に補足できたかどうかを個数レベルで構造情報と連動して捉えられうようになった。この知見は現在主流になりつつある３次元アトムプローブの基礎情報ともなるものである。