Phase transition of Ice detemined by maganetic measurement

2014 Fiscal Year Final Research Report

• Project/Area Number: 25610156
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Petrology/Mineralogy/Economic geology
• Research Institution: Osaka University
• Principal Investigator: KONDO Tadashi 大阪大学, 理学(系)研究科(研究院), 教授 (20252223)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Keywords: 氷天体 / 相転移 / 磁化率 / 低温高圧

Outline of Final Research Achievements

Water ice is universal material in space and has fifteen polymorphs reported so far. In this study, we tested a possibility of new method for studying structural change of ice using magnetic measurement. Experiments were conducted in Superconducting Quantum Interference Device magnetometer (SQUID, MPMS-7, Quantum design). We measured the magnetic moment of ice at temperature below room condition and/or at high-pressure condition to 0.2GPa. Pure water or salted water was used as starting sample. After accurate evaluation of magnetic moment of surrounding materials, solid-liquid transition of sample was detected with abrupt decrease of magnetic susceptibility. In the case of salt water, magnetic susceptibility decreased gradually with a temperature. In the high-pressure run, we found another jump in the profile. The condition was close to solid- solid phase boundary proposed. In this way, we successfully detected phase transition between liquid and solid in pure H2O and binary system.

Free Research Field

固体地球科学