**9. References**

162 Macro to Nano Spectroscopy

N-H 1500-1560

N-H 3300-3500 C-N 1000-1250 NH2 1550-1650 NH2 & N-H 660-900

O-H 3550-3600 C=N 1665± 15 N-O 945± 15

aromatic 1250± 50

Si-H 2100-2360 Si-OR 1000-1110 Si-CH3 1250± 10

nitro 1530± 20;1350± 30

950-1250

2100-2270

**Class Group Wavenumber (cm-1)**

Nitriles C≡N 2240-2260

Amine oxide (N-O) aliphatic 960± 20

N=O nitroso 1550± 50

Thiols S-H 2550-2600 Esters S-OR 700-900 Disulfide S-S 500-540 Thiocarbonyl C=S 1050-1200 Sulfoxide S=O 1030-1060

Sulfone S=O 1325± 25; 1140± 20

Sulfonyl chloride S=O 1365± 5;1180± 10 Sulfate S=O 1350-1450

Table 1. Schematic representation of the Infrared Group Frequencies classification

Alkyl bromide C-H 667

Sulfonic acid S=O 1345

Phosphine P-H 2280-2440

Phosphonic acid (O=)PO-H 2550-2700 Esters P-OR 900-1050 Phosphine oxide P=O 1100-1200 Phosphonate P=O 1230-1260 Phosphate P=O 1100-1200 Phosphoramide P=O 1200-1275


Isocyanates,Isothiocyanates, Diimides, Azides, Ketenes

**Oxidized Nitrogen Functions**

**Nitrogen compounds**

Amines

Oxime **(=NOH)**

**Sulfur compounds**

**Phosphorous compunds**

**Silicon compounds**

Silane

E.O. Brigham: "The Fast Fourier Transform", Prentice-Hall, Inc., 1974


**10** 

*Hangzhou, China* 

**Application of Infrared Spectroscopy in** 

*State Food and Drug Administration Medical Device Supervising and* 

*Testing Center of Hangzhou Zhejiang Insitute for the Control of Medical Device,* 

Infrared Spectrum (IR) is mainly used to study molecular structure and composition in substances and thus is also called molecular spectrum. When the sample is exposed to infrared light with continuously changing frequency, the molecule absorbs irradiation of certain frequencies and is subject to vibration or rotation, thus to cause the change of dipole moment. The molecule's transition from normal state to excited state weakens the intensity of the corresponding transmitted light in the absorption region, then the infrared software is used to obtain the IR spectrum. Started in 1970, Fourier Transform Infrared Spectroscopy (FTIR) was of high resolution and high scanning speed. It was not only limited to middle infrared (MIR), Spectrum ranges ultraviolet to far infrared section with the assistance of the beam splitter. The main direction of modern analysis, study and development is to combine technology of FTIR with that of the other instrument. For example, FTIR-TGA (Thermogravimetry Analysis) can be used to obtain thermogravimetric curve as well as the IR spectrum of the weight loss material, thus to determine the real composition of vapor

Ultraviolet and visible absorption spectrum are usually used to study unsaturated organic matter, especially the organic compounds with conjugated system. However, infrared spectroscopy mainly studies chemical compounds with change of dipole moment during vibration. Thus, almost all organic compounds, except single atoms and homonuclear molecule, absorb in the infrared spectrum region. Except for optical isomers, some high polymer of high molecular weight and compounds with slight difference in molecular weight, two compounds of different structure are unlikely to have the same infrared spectrum. Wave number position, number of wave peaks of infrared absorption band and the intensity of absorption band indicate the characteristics of the molecular structure, and thus can be used to identify the structural composure of the unknown objects or its chemical groups. The absorption intensity of the absorption band is related to the contents of the molecular composition or the chemical groups and can be used for quantitative analysis and purity identification. Infrared spectrum analysis has distinctive characteristic and can be used to test gas, liquid and solid samples. Lie other analysis methods, it can be used for qualitative and quantitative analysis and is one of the effective methods for chemical

generated in the various weight loss stages and the decomposition process.

compound identification and molecular structure elucidation.

**1. Introduction** 

**Biomedical Polymer Materials** 

Zhang Li, Wang Minzhu, Zhen Jian and Zhou Jun

A.Streitweiser, Jr., C. H. Heathcock. Introduction to Organic Chemistry. 2nd Ed. New York: Macmillan Publishing Co., Inc., 1981. Introductory organic text with a section on IR spectroscopy. Includes spectroscopic information as each family is presented.
