[2] [2] G. E. Kugel, F. Brehat, B. Wyncke et al.. The vibrational spectrum of a KTiOPO4 single crystal studied by Raman and infrared reflectivity spectroscopy. J. Phys. C: Solid State Phys., 1988, 21(32): 5565～5583

[3] [3] E. J. Baran, R. C. Mercader, G. E. Narda et al.. Spectroscopic investigation of CaFeSn(PO4)3. Solid State Commun., 1986, 58(8): 503～506

[4] [4] S. Ledain, A. Leclaire, M. M. Borel et al.. A molybdenum V diphosphate with the KMoOP2O7 structure: NaMoOP2O7. J. Solid State Chem., 1996, 124(1): 24～28

[5] [5] L. Seguin, M. Figlarz, R. Cavagnal et al.. IR and Raman spectra of MoO3 and MoO3XH2O. Spectrochemica Acta part A, 1995, 51(8): 1323～1344

[6] [6] H. M. Kim, T. Fukumoto, S. Hayashi et al.. Raman study of crystal structure of gas-evaporated MoO3 microcry stals. J. Phys. Soc. Jpn., 1994, 63(6): 2194～2201

[7] [7] B. H. Loo, J. N. Yao, H. D. Coble et al.. A Raman microprobe study of the electrochromic and photochromic thin films of MoO3 and WO3. Appl. Surf. Sci., 1994, 81(2):175～181

[8] [8] F. D. Hardcastle, I. E. Wachs. Determination of Mo O bond distances and bond orders by Raman spectroscopy. J. Raman Spectr., 1990, 21(10): 683～691