傅立叶变换红外（FT | 合法醫療器材資訊網

关于傅立叶变换红外光谱（FTIR）.过去，样品的分析是一步一步的，即用不同的单波长(色散)照射样品。而FT-IR则一次收集所有波长的光谱数据。在这里，连续 ...

To avoid total absorbance, the sample is diluted which allows the IR light to pass through the sample without being absorbed too strongly. The substance that is used to dilute the sample should not absorb IR light in the same range as the sample. Otherwise, the substance used to dilute the sample would also appear on the resulting spectrum.

To analyze a liquid sample, the liquid is diluted with a solvent. The usual choice is carbon tetrachloride (CCl4). To analyze a solid sample, the solid must be ground and mixed with another solid, typically potassium bromide (KBr) which does not absorb light in the MIR range. The resulting mixture is pressed into a pellet to be analyzed. Alternatively, the sample can be very thinly sliced and placed on a KBr window. This sample preparation can only be skipped if the sample is extremely thin (< 15 µm).

The sample preparation process for transmissi...