测量了十四个稀土五磷酸盐(除P_mPP外)和YPP晶体的红外吸收光谱、反射光谱和拉曼光谱。用基团频率对所观察到的振动谱带进行了归属。发现它们的光谱按晶型可分为三类,与X线衍射的结果一致。观察到O—P—O伸展振动、变角振动和Ln—O伸展振动频率随稀土原子序数增加而增加的线性关系。认为Ln—O键合具有共价性质。讨论了O—P—O振动带向高频移动的可能原因。 The infrared absorption spectra, reflection spectra and Raman spectra of fourteen rare earth pentaphosphates (except P_mPP) and YPP crystals were measured. The observed vibrational bands are assigned by the group frequency. Their spectra were found to be classified into three groups by crystal form, consistent with the results of X-ray diffraction. O-P-O stretching vibration, angular vibration and Ln-O stretching vibration frequency were observed to increase linearly with the increase of rare earth atomic number. Ln-O bonding is considered to have covalent properties. The possible reasons for the O-P-O vibration band moving toward high frequency are discussed.