Physical Properties of ReSe2 and ReSe2:Au and ReSe2:Ag under High Pressure

• Main Author: 張玉萍
• Other Authors: 林志明
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/29303129942483947801

碩士 === 國立新竹教育大學 === 數理教育研究所 === 100 === Summary This summary is to discuss the sample ReSe2 and gold-doped and silver-doped has been investigated to 10.50GPa、9.50GPa、8.04GPa through the angular analyze (Angular-dispersive X-ray diffraction, ADXRD) high pressure experiment,respectively. The obtained datas,to analyze the variability of crystal lattice. Shows there are High-pressure phase occurred under ReSe2 at 9.98GPa, ReSe2:Au at 8.52GPa, ReSe2:Ag at 7.46GPa. Under the high pressure, the result of the highest compression rate of the unit cell parameters is the c-axis among these three samples. The second is a-axis. and the lowest is b-axis. Because of the layer structure. Along the c-axis (001) is the combine between layer and layer. There is only a weak Van der Waals existed between layer and layer. And there is a stable metal bond link between the b-axis and diamond chain mutually parallel. Therefore, as long as a little pressure adding might caused the slide between layer and layer. The high pressure experiments is before the phase transition pressure. Because the pressure increase on ReSe2 , so the unit cell parameters decreased, under the trend of β increase and c decrease. There is a counterclockwise whirling occurred while Se circle Re4.. Gold-doped ReSe2 has a non-standard status. Because the decrease on c and the change on α、γ, there is a whirling trend from clockwise to counterclokwise. There is less regular increase-decrease on the unit cell parameters silver-doped ReSe2 . The stability is lower than the gold-doped ReSe2 . Gold-doped ReSe2 and silver-doped ReSe2 have abnormal situation. Because of the c-decrease and the α、γ change, have the tendency from counterclockwise to clockwise and counterwise rotating or distorting. Doped silver ions, the stability than gold doping ReSe2 low. To use three rank Birch–Murnaghan solidstate formula to figure out the bulk modulus of these three samples, the results are: 31GPa、 35 GPa、16 GPa。