稀土离子光谱探针的研究:EuS4N配合物在低温下的可逆相变

Lanthanide Ion Luminescence Probe:Low Temperature Phase Transition of EuS4N Complex

从配合物EuS4N低温荧光光谱的研究 ,可得到温度变化时配合物结构变化多方面的信息。从光谱转变的温度可知道结构变化对应的温度在约 16 0K ,对 5D0 → 7F0 跃迁谱峰的分析可推知结构变化前后Eu3 +配位结构的情况。从发光强度与温度变化的速度、方向的关系可推测结构变化时的热效应 ,并通过对样品温度的直接测量进行了验证。对配合物发生这种结构变化的可能原因进行了分析。研究表明 ,Eu3 +离子光谱探针在低温晶体结构的研究中具有某些特殊的优点 ,可作为单晶X

Fluorescence, spectrum of EuS4N complex at low temperature is very different from that at room temperature. When temperature changes, shapes of both excitation and emission spectra change dramatically at about 1 60 K, which is taken as an indicator of the structural change of EuS4N. Peak splitting of D-5(0)-->F-7(0) also indicates that there are two different types of coordination structure for Eu3+ ions at low temperature, while only one at room temperature. Thermal effect for the structure transition is also deduced from the relation between fluorescence intensity and temperature changing manner. These results were in good accordance with directly measurement on sample temperature. The reason for the structure change is also discussed from the structure of the EuS4N complex. This study proved that lanthanide luminescent probe, as a complementarity to X-ray diffraction technique, should be an effective tool in low temperature crystal structure study.