拉曼和红外光谱之间有什么区别？

Raman and IR spectroscopy are complementary techniques used for fingerprinting of molecules.拉曼光谱学提供了显着优势超过IR和其他光谱技术。

Both Raman and IR spectra result due to changes in vibration modes of molecules. However, only those vibration modes which result in changes in the dipole moment of a module are IR active and those that result in change in polarizability are Raman active. IR and Raman activities are related to symmetry of molecules and can be expressed in terms of Rule of mutual exclusion which states that for a molecule having a centre of symmetry the Raman active vibrations are IR inactive and vice versa. However, this rule is not applicable to molecules having no centre of symmetry. In such case vibrations may be both Raman as well as IR active. The rule is valuable in establishing the structure of a molecule such N2O. The spectra of the molecule.suggests that the molecule does not have a center of symmetry. It can be concluded that the molecule has a structure N-N-O and not
非。

两种光谱技术之间的差异如下：

• 拉曼光谱是由于振动分子散射光导致的，而红外光谱是由振动分子吸收而引起的。
• 拉曼活性是由于分子的极化性的变化而导致的，而IR活性是由于偶极矩的变化而导致的
• 高强度激光的单色光束can be used in UV, visible or IR regions in Raman measurements whereas in IR spectroscopy the range is limited to IR frequencies
• 在拉曼散射的情况下，观察到与入射光束的方向成直角，而在IR的情况下，吸收信号的测量与入射光束相同。
• 拉曼技术无损。可以在玻璃容器中直接测量样品，也可以在药品样品中测量样品。IR技术需要使用KBR或CSI粉末进行固体样品制备，但虽然配件，例如哈特允许直接观察液体，膜和凝胶。
• 拉曼技术中的激光源高度强烈，这些激光源促进了将相干光束聚焦在小样品区域或非常小的样品体积上。只有有限的样品数量可用，这是一个关键优势
• 在存在强烈的雷利光散射成分的情况下，必须高度扩增Stoke信号。这导致拉曼光谱仪的成本更高。与该技术提供的好处相对于更高的成本可以很容易地证明是合理的。