You have to do several measurements if you want to determine the chemical compounds and bonding within a sample. I would start with NMR and FTIR measurements, but you may also need to perform mass spectrometry, UV-VIS, EDX and XRD for a complete characterization.

Dear Natalia Lopez-Barbosa UV-Vis will give only the band gap, so it will difficult to collect the information about the nature of compounds, XRD can give the information of crystalline materials only, if there will be any inorganic compound it will not work for that, FTIR gives nature of bounding(stretching, bending or vibrations) between bounds. I want to collect the information about the nature of chemical compounds present in leaves or in vegetables.

How can i collect that information from FTIR or NMR

There is no one single technique that will give you the precise composition of a sample. You need to perform different measurements and correlate the data to try to deduce the composition of your sample. FTIR can give you an idea of the functional groups that your sample might contain. Similarly, NMR spectroscopy will give you an idea of the proportions and nature of the protons in your sample, as well as their environment. By performing different techniques in the NMR you can conclude the presence of certain groups by the relaxation times. You can also use a PGSE experiment to determine the diffusion coefficients associated to your different peaks and compare them with the literature to close up the possible compounds in your sample. Other techniques will only increase the amount of information and might let you have a better estimation of what is in your sample. It might be easier if you have an initial guess of what your sample contains. You might also try to separate the different groups that might be in your samples. For example, you might try to isolate all sugars or all proteins and then analyse these "subsamples" separately to dimminish the cross signals of your original samples. 

Thanks dear Natalia Lopez-Barbosa for discussion 

Personally I would go with Mass spectrometry technique. Nowadays it is possible to get a triple quadrupoles (quad) if molecules are smaller. In those type of MS, it its possible to use the middle quad as a reaction chamber where scanning of daughter ions allows you to determine the structure of the molecules. This is used for genomics, lipidics in the pharmaceutical industries. The challenge is in the production of ions since MS is a ratio mass over charge. You have to go through an soft extraction process from your sample so that no molecules change their structure. Using isotopic ratio, this become the way of determining the structure of a compound.  

The Laser Spectrum has to be within the violet range....blue-violet.. whatever the spectrum of it is in numbers...