图谱解析.ppt

图谱解析Interpretation of Spectra
任课教师:顾小红
电话: 5864482(8482)
Introduction
Spectroscopy
the cornerstone of anic chemistry of the second half of the twentieth century.
Using spectroscopic techniques to solve structural problems.
Ultraviolet spectroscopy (UV), in 1930s
Infrared spectroscopy (IR), in 1940
functionality
Mass spectrometry (MS), in 1950s
molecular formula
Nuclear ic resonance spectroscopy (NMR), in 1950s
Molecular skeleton
The pace of progress in structure determination
1960s, the advent of the Varian Associates A-60 spectrometer
proton NMR
1970s, the development of the FT instrument
carbon-13 NMR (CMR)
1990s, ‘two-dimensional’(2D) NMR, a daughter of puter revolution
Three waves of NMR
UV to detect conjugated systems, the promotion of electrons from the ground state to the excited state
IR to detect and identify the vibrations of molecules, especially the characteristic vibrations of the double and triple bonds present in many functional groups
NMR to detect changes in the alignment of nuclear s in strong ic fields, such nuclei as 1H, 13C, 15N, 19F, P31 etc.
MS to measure the mass-to-charge ratio anic ions
Where UV, IR, NMR
rely on the selective absorption of ic radiation
Spectroscopic methods
X-ray diffraction to pinpoint centres of high electron density (. the atoms)
Microwave absorption to measure molecular rotations
Electron spin resona