本實驗的目的為驗證前人在四面體結構的複鹽類之高壓拉曼研究中發現之系統性現象。實驗發現，某些複鹽類如磷酸鹽類之中心離子的等價電位﹝e.v.﹞與中心離子群的對稱拉張振動模隨壓力的變化﹝dν/dP﹞呈反比之關係。因此對與磷酸鹽類具等價電位的砷酸鹽類做高壓拉曼實驗，期以驗證兩者的dν/dP值是否相近。本次研究對五種砷酸鹽類礦物﹝Conichalcite、Adamite、Olivenite、Clinoclase、Euchroite﹞做高壓實驗。利用鑽石高壓砧為壓力機，並以紅寶石螢光測壓法測量壓力。得到之實驗結果中證實砷酸鹽對稱拉張振動模之dν/dP值與磷酸鹽相符合，除Euchroite是因晶格中含較多H2O而造成其ν1之dν/dP值較大。

　　大多數砷酸鹽的ν1、ν3振動模在常壓下無法區分，但在高壓下則分成明顯的兩個或以上的獨立峰。前人研究中﹝Frost，2002﹞常溫常壓下的Olivenite及Clinoclase都只定出二個對稱拉張拉曼振動模，本實驗中則經仔細的比對後，分別定出三個及五個對稱拉張拉曼振動模。

　　ν1振動模通常是複鹽類中最強的振動模，但在砷酸鹽中之Olivenite及Euchroite發現較強的拉曼峰卻是ν3振動模，其dν/dP值顯得較低，而其ν1振動模則在高壓下具有相當於一般磷酸鹽之dν/dP值。

　This goal for this study is to justify the recent discovery that systematic relationship exists between the equivalent valence and the strength of its stretching mode in a complex ion. Previous high-pressure experiments provided evidence that the wavenumber of symmetrical stretching mode (ν1) of the central ions in complex salts, such as the P-O bond in a phosphate has an inverse relationship with their equivalent valancy (e.v.). (dν1/dp). Therefore, it is important to conduct high-pressure Raman spectroscopic study in arsenates with a equivalent valancy equals to phosphates, in order to test if the variation of ν1 with pressure (dν1/dP) of the two complex salts is similar. In this study, five Cu-bearing arsenate minerals (i.e., conichalcite, adamite, olivenite, clinoclase, euchroite) were investigated. Samples were loaded and compressed to pressures up to 15 GPa in a diamond anvil cell and pressure was measured by ruby fluorescence method. The results indicate that the values of dν1/dP in arsenates are similar to phosphates. We also found that the presence of O-H results a larger value of dν1/dP in hydrous arsenates such as euchroite.
　
　In most arsenates, ν1 and ν3 modes cannot be distinguished at the ambienty conditions. However, when under pressure, they show two or more independent peaks which can be identified spearately. Moreover, we observed more symmetrical stretching modes in some aresenates. For instance, we observed three and five modes in olivenite and clinoclase, respectively, which were more than two modes as reported by Frost (2002).

　The ν1 mode is usually the most intense vibration mode in the complex salts. But in olivenite and euchroite, the ν3 mode is more intense than the ν1 mode. In contrast with dν1 /dP which are similar to those of phosphate, dν3/dP has a value much lower than dν1 /dP.

Berry L. G. (1951) Observations of conichalcite, cornwallite, euchroite, liroconite and olivenite. Am. Mineral, 36, 484-503.

Chisholm J. E. (1985) Cation Segregation and the O-H Stretching Vibration of the Olivenite-Adamite Series. Phys Chem Minerals, 12, 185-190.

Eby R. K., and F. C. Hawthorne (1989) Euchroite, a Heteropolyhedral Framework Structure. Acta Cryst., C45, 1479-1482.

Fadini A., and F. M. Schnepel (1989) Vibrational spectroscopy-methods and applications. Elhs Gorwood Limited, England, 205P

Finney J. J. (1966) Refinement of the crystal structure of euchorite, Cu2(AsO4)(OH).3H2O. Acta Cryst., 21, 437-440.

Frost R. L., Williams P. A., Martens W. N., Kloprogge J. T., and P. Leverett (2002) Raman spectroscopy of the basic copper phosphate minerals cornetite, libethenite, pseudomalachite, reichenbachite and ludjibaite. J. Raman spectrosc., 33, 260-263.

Frost R. L., Kloprogge T., Weier M. L., Martens W. N., Ding Z., and H. G. H. Edwards (2003) Raman spectroscopy of selected arsenates-implications for soil remediation. Spectrochimica Acta, Part A, 59, 2241-2246.

Ghose S., Fehlmann M., and M. Sundaralingam (1965) The crystal Structure of Clinoclase, Cu3AsO4(OH)3. Acta Cryst., 18, 777-787.

Hill R. J. (1976) The crystal structure and infrared properties of adamite. Am Mineral, 61, 979-986.

Huang E. (1992) Pressure measurements in diamond anvil cell by ruby fluorescence method and some application. J. Geol. Soc. China, 35, 2, 135-150.

Lipinska-Kalita K. E., Kruger M. B., Carlson S., and A. M. Krogh Andersen (2003) High-pressure studies of titanium pyrophosphate by Raman scattering and infrared spectroscopy. Physica B, 337, 221-229.

Mao H. K., and P. M. Bell (1978) Megabar Cell, Carnegie Inst. Wash. Year Book, 77, 904-908.

Mcillian P. (1985) Vibration spectroscopy in the mineral sciences, Mineralogical Society of American, 14, pp, 9-63, edited by Kieffer, S.W. and Navrotsky, A.

Paques-Ledent M. Th., and P. Tarte (1973) Vibrational studies of olivine-type compounds-II Orthophosphates, -arsenates and –Vanadates AIBIIXVO4. Spectrochimica Acta, 30A, 673-689.

Ravindran T. R., Akhilesh K. A., and T. A. Mary (2001) High-pressure Raman spectroscopic study of zirconium tungstate. J. Phys. Condens. Matter 13, 11573-11588.

Shannon R. D., and C. Calvo (1973). Crystal structure of Cu5V2O10. Acta Cryst., B29, 1338-1345.

Toman K. (1977) The Symmertry and Crystal Structure of Olivenite. Acta Cryst., B33, 2628-2631.

Toman K. (1978) Ordering in Olivenite-Adamite Solid Solutions. Acta Cryst., B34, 715-721.

Valentín G. B., Mercedes T., Amaya A., Mercedes C., and N. Javier (2003) Diamond as pressure sensor in high-pressure Raman spectroscopy using sapphire and other gem anvil cells. J. Raman Spectrosc., 34, 264–270.

Martens W. N., Forst R. L., Kloprogge J. T., and P. A.Williams (2003) The basic copper arsenate minerals olivenite, cornubite, cornwallite, and clinoclase: An infrared emission and Raman spectroscopic study. Am Mineral, 88, 501-508.

Xu J. A., Mao H. K., and J. H. Russell (2002) The gem anvil cell: high-pressure behaviour of diamond and related materials. J. Phys. Condens. Matter 14, 11549–11552.

王冠益 (2001) 摩星石砧：一種新型的高溫高壓砧。國立成功大學地球科學研究所碩士論文, 56頁。

李玉玲 (1999) 磷酸鹽礦物-磷灰石、獨居石之高溫、高壓光譜研究。國立成功大學地球科學研究所碩士論文, 117頁。

李佩倫 (2000) BaSO4-PbSO4固溶系列之高溫高壓相變研究。國文成功大學地球科學研究所博士論文,139頁。

余樹楨 (1989) 晶體之結構與性質。渤海堂文化事業有限公司, 台北, 569頁。

徐濟安、毛河光及P. M. Bell (1987) 百萬氣壓下強壓校準及5.5Mbar靜強壓的獲得, 物理學報, 36, No. 4, 501-510。

陳燕華 (1998) 高壓下硫酸鋇、硫酸鍶二元相系之晶相轉變研究。國立成功大學地球科學研究所碩士論文, 60頁。

黃克駿 未發表。

黃怡禎譯 (2000) 礦物學。地球科學文教基金會, 台北, 686頁。

黃慶祥 (1997) CaSO4-H2O系統內礦物之高壓相變研究。國立成功大學地球科學研究所碩士論文, 72頁。

楊聖恩 (1994) CaCO3之高壓拉曼光譜研究。國立台灣大學地質學研究所碩士論文, 117頁。