Patent ID: 8723520

Claim:
A method of controlling a static magnetic field in an NMR spectrometer in such a way that the temperature inside a sample tube can be controlled, said method comprising the steps of: setting the temperature inside the sample tube to a given temperature; finding a distribution of resonance frequencies within the sample tube by NMR measurements for each of two peaks existing in an NMR spectrum of a calibration sample; finding a distribution of chemical shift differences within the sample tube for the two peaks, based on a difference in resonant frequency distribution between the two peaks; finding a temperature distribution across the sample tube at the set temperature based on the distribution of the chemical shift differences for the two peaks; finding a distribution of chemical shifts within the sample tube at the set temperature of a solvent used for the measurements based on the temperature distribution across the sample tube at the set temperature; and doing shimming using magnetic field gradients based on the distribution of the chemical shifts of the solvent.