ICMRE2025 Abstract template
Simple organics at Extremes: A case study of formamide
Rui Zhang^1,2, Thomas Meier^2,3, Renbiao Tao^2
1 School of Earth and Space Sciences, Peking University, Beijing
² Center for High Pressure Science & Technology Advanced Research, Beijing
³Shanghai Key Laboratory MFree, Institute for Shanghai Advanced Research in Physical Sciences,  Shanghai
rui.zhang@hpstar.ac.cn
Formamide is the simplest molecule containing C, H, O, and N, four essential elements of life, and features an aminde functional group involved in peptide bond formation, making it a key molecule in prebiotic chemistry¹. Investigating the physical and chemical properties of formamide under high temperature and pressure not only aids in understanding its stability in extreme environments but also provides insights into the formation of complex organic molecules. Furthermore, it serves as an important basis for studying deep Earth chemical processes and exploring the origin of life. While previous studies have extensively examined the formation mechanism of formamide and its role in generating prebiotic molecules^2,3, its behavior under high temperature and pressure remains unclear. In this study, we employed diamond anvil cells (DACs) to conduct in-situ nuclear magnetic resonance (NMR) and Raman spectroscopy to investigate changes in the electronic and atomic energy landscape.
The experimental results show that:
(1) Raman spectroscopy shows an anomalous negative melting curve under pressure within a narrow temperature range.
(2) high pressure NMR relaxomtery⁴ shows that NH₂ amide groups undergo a structural change to imide NH groups, possibly associated to a partial hydrogen-bond symmetrisation at pressures above 70 GPa.
(3) Within the temperature range of 50-200 °C and pressure range of 0.5-13 GPa, in-situ Raman spectroscopy shows the sample going through a multitude of states: liquid , solid-liquid coexistence, and two emerging high-pressure phases.
Overall, under high temperature and pressure, the local environment of formamide undergoes significant changes, possibly related to the restructuring of the hydrogen bonding network and changes in functional groups.
[1] Beyazay, T., Martin, W. F. & Tüysüz, H. Direct synthesis of formamide from CO2 and H2 O with nickel–iron nitride heterostructures under mild hydrothermal conditions. J. Am. Chem. Soc. 145, 19768–19779 (2023).
[2] Saladino, R., Crestini, C., Pino, S., Costanzo, G. & Di Mauro, E. Formamide and the origin of life. Phys. Life Rev. 9, 84–104 (2012)
[3] Saladino, R., Bizzarri, B. M. & Mauro, E. D. Determinism of formamide-based biogenic prebiotic reactions. Phys. Life Rev. 51, 243–251 (2024)
[4] Meier, T., Yang, M., Zhou, Y., Fu, Y., Zhang, R., Wang, Z., Zheng, T., Jana, R., & Nakagawa, T.  muT2-NMR: Micro-Scale Correlation Relaxometry for in-situ High-Pressure Nuclear Magnetic Resonance. Matter and Radiation at Extremes, under review,(2026).
 

formamide,high pressure and high temperature (HPHT)