 However, since we are dividing Hz by MHz, the resulting number would be too small, and thus it is multiplied by a million.This operation therefore gives a locator number called the "chemical shift" with units of parts per million.In general, chemical shifts for protons are highly predictable since the shifts are primarily determined by simpler shielding effects (electron density), but the chemical shifts for many heavier nuclei are more strongly influenced by other factors including excited states ("paramagnetic" contribution to shielding tensor).