Factors Affecting Chemical Shift in Proton NMR Spectroscopy
- Electronegativity: more electronegative element leads to deshielding of protons and signal appears at downfield and vice versa.
- Anisotropy effect: those compounds which are having a double or triple bond involve pi-electron which produces an induced field that may change the position of electrons and hence lead to shielding or deshielding.
- Hydrogen bonding: it increases the chain length which results in the deshielding of protons and shifted downfield in the spectrum. If it decreases the shielding of protons and upfield shifting will be there.
- Vander Waal deshielding: In the complex molecules, it may be possible that some protons may cause steric hindrance which may lead to the deshielding of protons.
