TY  - JOUR
AU  - Mondal, Anshuman
AU  - Husband, Rachel
AU  - Liermann, H.-P.
AU  - Sanchez-Valle, Carmen
TI  - Equation of state of ammonia dihydrate up to 112 GPa by static and dynamic compression experiments in diamond anvil cells
JO  - Physical review / B
VL  - 107
IS  - 22
SN  - 2469-9950
CY  - Woodbury, NY
PB  - Inst.
M1  - PUBDB-2023-03914
SP  - 224108
PY  - 2023
AB  - Understanding the high-pressure behavior of ammonia hydrates is relevant for modeling the interior of solarand extrasolar icy bodies. We present here the results of high-pressure x-ray diffraction studies on ammonia-dihydrate (ADH) at room temperature (298 K) up to 112 GPa, employing both static and dynamic compressionexperiments performed in diamond anvil cells. The derived pressure-volume (P-V) compression curves arein excellent agreement regardless of the compression technique. In contrast to early theoretical predictions,our results indicate the stability of the disordered molecular alloy (DMA) phase, a body centered cubic (bcc)structure, and the absence of self-ionization in the investigated pressure range. By combining the P-V data fromseven different compression runs, we derive the first equation of state for ADH-DMA based on the third-orderBirch-Murnaghan formalism with best-fit parameters: V<sub>0</sub> = 23.96 ± 0.03 (Å<sup>3</sup> /molecule), B<sub>0</sub> = 9.95 ± 0.14 GPa,and B′<sub>0</sub> = 6.59 ± 0.03. The instantaneous bulk modulus directly derived from the quasicontinuous compressioncurves displays a smooth increase upon compression that further supports the absence of structural transitions.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:001058029800001
DO  - DOI:10.1103/PhysRevB.107.224108
UR  - https://bib-pubdb1.desy.de/record/586486
ER  -