A study on intermolecular energy potential in a polar molecule by multi-spectroscopy using acoustic and electromagnetic waves

2020 Fiscal Year Final Research Report

• Project/Area Number: 17H04908
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Single-year Grants
• Research Field: Thermal engineering
• Research Institution: National Institute of Advanced Industrial Science and Technology
• Principal Investigator: Kano Yuya 国立研究開発法人産業技術総合研究所, 計量標準総合センター, 主任研究員 (90510040)
• Project Period (FY): 2017-04-01 – 2021-03-31
• Keywords: 音波 / 電磁波 / 音速 / 誘電率 / 分子間ポテンシャル / 双極子モーメント / 分極率 / ビリアル係数

Outline of Final Research Achievements

For the aim of the study on the intermolecular potential energy of a polar molecule, a new multi-spectrometer with a cylindrical acoustic-microwave cavity resonator was developed in this study. Using the developed multi-spectrometer, speed-of-sound and dielectric relative permittivity were simultaneously and accurately measured for a polar molecule gas in wide ranges of temperature and pressure. The electrical polarity of the polar molecule was evaluated by using the measured data, and the virial coefficients were calculated on the basis of Stockmayer potential model in combination with the corresponding state principle. Density was successfully derived from the present virial coefficients in wide ranges of temperature and pressure. The developed multi-spectrometer with the proposed data analysis method enables a precise multi-property evaluation for polar molecules.

Free Research Field

熱力学

Academic Significance and Societal Importance of the Research Achievements

本研究で開発したマルチスペクトロメータを用いることで，音速および誘電率を同時に高精度計測することができ，得られたデータの解析から理想気体状態の定圧比熱，エンタルピー，双極子モーメント，分子分極率などを求めることができる．さらに，本研究で提案する分子間ポテンシャルを対応状態原理により表現したビリアル係数算出モデルを用いることで，密度も正確に導出することができる．これらの計測技術やデータ解析手法を応用することで，冷媒など作動流体について迅速かつ高精度な多重物性評価を実現することができ，熱エネルギー機器の省エネ化や温室効果ガス削減などの波及効果が期待できる．