For energetic materials, the lattice vibration modes in the 6 THz (200 cm−1) range are very sensitive to structural changes caused by external temperature and pressure changes. Therefore, mid- and far-infrared vibrational spectroscopy can be used as a powerful tool to study high-pressure phase transitions in these materials. We have obtained high-pressure vibrational spectra of hydrazine nitrate, using mid- and far-infrared ultra-broadband spectroscopy, whose broadband was generated by air plasma, combined with a diamond anvil cell (DAC). The crystal structure of hydrazine nitrate, as well as the infrared spectrum, were calculated by using the first principle method. Based on the calculation, the intermolecular interactions were analyzed. Combined with the experimental results, it was revealed that the structural changes under pressure alter the strength of intermolecular hydrogen bonds and van der Waals interactions, which in turn affects the low-frequency vibrational modes. And by analyzing the vibrational spectra, we observed the phase transition process of hydrazine nitrate.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |