In the metal complexes, differentiate between coordinated and no-coordinated water molecules using a thermogravimetric analysis. In this analysis, 50 to 100 'C is the non coordinated water and 100 to 150 'C is the coordinated water molecules.
In the metal complexes, differentiate between coordinated and no-coordinated water molecules using a thermogravimetric analysis. In this analysis, 50 to 100 'C is the non coordinated water and 100 to 150 'C is the coordinated water molecules.
The best way to differentiate between coordinated and non coordinated water molecule is thermogravimetric analysis. The non coordinated molecules gives and endothermic peaks at temprature ranging between 50-70' C and coordinated molecules appear as endothermic peaks at around 100-120'C. TG in combination with DTA.
It is also possible to differentiate the same by spectroscopic methods such as IR and UV visible
It depend on valences of metal and strength of nucleophilicity of other ligands. You can found this without any analysis.
If you the complex as a solid, the best way is thermogarvimetry. the loss of both kind of water molecules should occur at different temperature. Spectroscopy can also help
IF you have both type of water within the same compound, vibrational spectroscopy can give some possibility to distinguish them. The deformation bands and libration bands might be different, but it depends on the strength of coordination, number of waters, position, etc.
TG-DTG is the best technique to differentiate the non-coordinated (70-100 oC) and coordinated water (100-150 oC) molecules. However, UV-Vis spectroscopy can also be used. If the water molecules get coordinated, you can assume from the geometry of complexes which derives from d-d transition. It further helps to find out the coordination number. From the coordination number, we can partly say whether the water molecules are present inside or outside the coordination sphere.
A broad peak in the IR spectrum of complex in 3500- 3200 cm-1 region may suggest the presence of water molecules in the complex . The coordinated water molecules generally show characteristic peaks around 750 cm-1 due to ρr(H2O) and 650 cm-1 ρw(H2O). However, the presence of type of water molecules may be confirmed further by TG-DTG analysis.
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