硅灰石分子结构的FTIR谱

FTIR SPECTRA FOR MOLECULAR STRUCTURE OF WOLLASTONITE

提供了一种研究链状硅酸盐矿物红外吸收谱归属的实验方法.1Tr型普通硅灰石酸解产物的Fourier变换红外（Fourier transform infrared,FTIR）谱研究表明：根据FTIR谱随酸解时间延长的演变规律,硅灰石的FTIR谱中所有吸收谱带的归属均可确切指定.1Tr型普通硅灰石的FTIR谱归属为：1 085cm^-1吸收带是OT-Si-OT（桥氧）非对称伸缩振动产生的,1 060cm^-1和1 018 cm^-1吸收带是Si-OT-Si非对称伸缩振动形成的,967cm-1吸收带是OB-Si-OB（非桥氧）对称伸缩振动引起的,927cm^-1和902cm^-1吸收带是OT-Si-OB非对称伸缩振动产生的,681 cm^-1和645 cm^-1吸收带是Si-OB-Si对称伸缩振动吸收形成的,567cm^-1和509cm^-1吸收带是Si-OB弯曲振动吸收产生的,472 cm^-1吸收带是Si-OT弯曲振动吸收的结果,453 cm^-1吸收带是M-OT（M代表Ca）伸缩振动吸收产生的.另外,酸解产物的FTIR谱中799和1 160～1 250 cm^-1附近的吸收带提供了硅灰石酸解二氧化硅的有序度随酸解时间延长而逐渐增大的证据.

An experimental method was present for determining the origins of infrared absorption spectra of chain silicate minerals. Fourier transform infrared （FTIR） spectra of the acidolysis products of 1Tr-type wollastonite were measured with Nicolet Nexus FTIR spectroscopy. The results show that the origins of all the absorption bands of FTIR spectrum of wollastonite can be definitely assigned on the base of the evolvement features of the FTIR spectra of the products as the acidolysis time increased from 0 to 60 min. The origins of FTIR spectrum of 1Tr-type wollastonite are as follows： the absorption band at 1 085 cm^-1 represents the asymmetrical stretching vibrations of OT-Si-OT （OT represents the bridge oxygen） group; the absorption bands at 1 060 cm^-1 and 1 018 cm^-1 represent the asymmetrical stretching vibrations of Si-OT-Si group; the absorption band at 967cm^-1 represents the symmetrical stretching vibrations of OB-Si-OB （OB represents the non-bridge oxygen） group; the absorption bands at 927 cm i and 902 cm^-1 represent the asymmetrical stretching vibrations of OT-Si-OB group; the absorption bands at 681 and 645 cm i represent the symmetrical stretching vibrations of Si-OB-Si group; the absorption bands at 567 cm^-1 and 509 cm^-1 represent the bending vibrations of Si-OB group; the absorption band at 472 cm^-1 represents the bending vibrations of Si-OT group, and the absorption band at 453cm^-1 represents the stretching vibrations of M-OT （M represents Ca） group. In addition, the FTIR absorption bands at about 799 and 1 160-1 250 cm^-1 from the products provide an evidence that the degree of order of amorphous silica formed by the acidolysis of wollastonite is gradually improved as the time increased from 0 to 60 min.