最新ATRFTIR衰减全反射光谱的原理汇总
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➢ATR-FTIR has become a kind of beneficial tool and means for analyzing samples and surface properties.
➢ATR-FTIR has been applied to every realm such as spinning and weaving, quality testing , public security and so on.
ATR is used for surface analysis of solids and liquids.
ATR generally allows qualitative or quantitative analysis of samples with little or no sample preparation which greatly speeds sample analysis.
This can be achieved by pressing the sample down on the crystal.
Tinfoil
If the substance under study is a
liquid, it is simply dropped onto
the crystal, thereby obtaining
Then the mixture is pressed into a tablet which is then used in the analysis.
schematic illustration
➢Traditional IR does not work quite effectively , and for analyzing surface layer structure.
applications
Characterization of Surface Treatments of Cork Stoppers by FTIR-ATR
J. Agric. Food Chem. 2006, 54, 4932-4936
The paper proposed an analytical method for identification of the presence of surface treatments in cork stoppers.
tshaemcprlieti,cna1l
is the angle.
1 when exceeding the critical angle, we will get a totally reflection of the IR beam.
2 n1>n2 ,the crystal has a relatively high refractive index.
➢It extends beyond the surface of the crystal into the sample held in contact with the crystal.
rwefhraecrteivne2
ห้องสมุดไป่ตู้
is the index
refractive index of the of the crystal and θc is
The sample is put on top of the blue crystal.
The IR beam picks up a signal as it passes a few micron into the sample and creates an evanescent wave.
Light path in the ATR setup schematic illustration
The 2963 cm-1 band is due to CH3 and occurs in silicones exclusively as the only alkane.
Bands 1258, 1079, 1010and 787 cm-1 are specific of silicone. Bands 2963, 2916, and2850 cm-1, which are less specific, corresponding to C-H bonds, had intensities that differed greatly in both types of compounds
While the evanescent wave extends only 0.5-5 µm beyond the crystal surface and into the sample.
Therefore it is important to obtain good contact between the crystal and the sample.
optimal contact.
Equipment to push the
sample onto the crystal
Traditional IR spectroscopy need preparation of the sample.
First a couple of milligram of sample is mixed with about 200 mg of KBr powder.
ATRFTIR衰减全反射光谱的原理
Brief introduction of ATR
Attenuated Total Reflectance (ATR) is an IR sampling technique. It measures the changes in an infrared beam with totally internal reflection when it comes into contact with a sample.
How ATR Works
➢With ATR sampling we direct the IR beam into a crystal of relatively higher refractive index at a certain angle.
➢The IR beam reflects from the internal surface of the crystal and creates an evanescent wave.
➢ATR-FTIR has been applied to every realm such as spinning and weaving, quality testing , public security and so on.
ATR is used for surface analysis of solids and liquids.
ATR generally allows qualitative or quantitative analysis of samples with little or no sample preparation which greatly speeds sample analysis.
This can be achieved by pressing the sample down on the crystal.
Tinfoil
If the substance under study is a
liquid, it is simply dropped onto
the crystal, thereby obtaining
Then the mixture is pressed into a tablet which is then used in the analysis.
schematic illustration
➢Traditional IR does not work quite effectively , and for analyzing surface layer structure.
applications
Characterization of Surface Treatments of Cork Stoppers by FTIR-ATR
J. Agric. Food Chem. 2006, 54, 4932-4936
The paper proposed an analytical method for identification of the presence of surface treatments in cork stoppers.
tshaemcprlieti,cna1l
is the angle.
1 when exceeding the critical angle, we will get a totally reflection of the IR beam.
2 n1>n2 ,the crystal has a relatively high refractive index.
➢It extends beyond the surface of the crystal into the sample held in contact with the crystal.
rwefhraecrteivne2
ห้องสมุดไป่ตู้
is the index
refractive index of the of the crystal and θc is
The sample is put on top of the blue crystal.
The IR beam picks up a signal as it passes a few micron into the sample and creates an evanescent wave.
Light path in the ATR setup schematic illustration
The 2963 cm-1 band is due to CH3 and occurs in silicones exclusively as the only alkane.
Bands 1258, 1079, 1010and 787 cm-1 are specific of silicone. Bands 2963, 2916, and2850 cm-1, which are less specific, corresponding to C-H bonds, had intensities that differed greatly in both types of compounds
While the evanescent wave extends only 0.5-5 µm beyond the crystal surface and into the sample.
Therefore it is important to obtain good contact between the crystal and the sample.
optimal contact.
Equipment to push the
sample onto the crystal
Traditional IR spectroscopy need preparation of the sample.
First a couple of milligram of sample is mixed with about 200 mg of KBr powder.
ATRFTIR衰减全反射光谱的原理
Brief introduction of ATR
Attenuated Total Reflectance (ATR) is an IR sampling technique. It measures the changes in an infrared beam with totally internal reflection when it comes into contact with a sample.
How ATR Works
➢With ATR sampling we direct the IR beam into a crystal of relatively higher refractive index at a certain angle.
➢The IR beam reflects from the internal surface of the crystal and creates an evanescent wave.