Anharmonic coupling between fundamental modes in tetramethylurea

• Main Authors: Chen, Yuanzheng, Men, Zhiwei, Li, Juntao, Li, Zhanlong, Sun, Shengnan, Sun, Chengling, Gao, Shuqin, Li, Zuowei, Zhou, Mi
• Other Authors: School of Materials Science & Engineering
• Format: Article
• Language: English
• Published: 2014
• Subjects: DRNTU::Engineering::Materials
• Online Access: https://hdl.handle.net/10356/98746; http://hdl.handle.net/10220/19602
• Institution: Nanyang Technological University

In situ high pressure Raman spectra of tetramethylurea have been measured up to 25 GPa, liquid-solid and solid-solid phase transitions were detected at 0.2 GPa and 7.4 GPa, respectively. An unprecedented spectral phenomenon is the observation of a Fermi resonance between the fundamental modes. An ex...