Nucleating Silicate Analogues in Supersaturated Vapor

2019 Fiscal Year Final Research Report

• Project/Area Number: 18K13598
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 17010:Space and planetary sciences-related
• Research Institution: National Institute for Environmental Studies
• Principal Investigator: Ishizuka Shinnosuke 国立研究開発法人国立環境研究所, 環境計測研究センター, JSPS特別研究員 (20817788)
• Project Period (FY): 2018-04-01 – 2020-03-31
• Keywords: 核生成 / 相分離 / ダスト

Outline of Final Research Achievements

Nucleation, the creation of a new material phase from another, has long been enigmatic. Astronomical dust had been deemed to be formed from mother phase directly. I demonstrated that homogeneous nucleation of refractory oxide nanoparticles from vapor is multistep. Various nucleation pathways accompanied by changing chemical compositions, crystal structures, and shapes were elucidated.

Free Research Field

物理化学

Academic Significance and Societal Importance of the Research Achievements

これまでダストの結晶構造，形態は生成した時点の温度・圧力条件で決定すると考えられてきた．本研究では，気相からの核生成過程とその赤外スペクトルを直接的に調べることに成功した．本研究は，核生成した直後の粒子は，最終的な結晶とは化学組成，結晶構造，形態が異なる場合があることを示し，これまでの想定を覆した点に学術的な意義がある．