title: NMR spectroscopy for chemical analysis at low magnetic fields.
abstract: This chapter addresses the limits of low-field NMR spectroscopy for chemical analysis and will answer the question of whether high-resolution NMR spectroscopy for chemical analysis of solutions can be achieved with magnetic fields much lower than 0.1 T without losing the chemical information which at high field is derived from the chemical shift and the indirect spin-spin or J-coupling. The focus is on two major issues. First, the thermal spin population differences given by the Boltzmann distribution are small at low field and so is the signal-to-noise-ratio when starting measurements from thermal equilibrium. Second, the possibility of identifying chemical groups is explored at low magnetic fields where the chemical shift can usually no longer be resolved.
authors.affiliation: Institute for Technical Chemistry and Macromolecular Chemistry, RWTH Aachen, 52056, Aachen, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Glöggler
authors.forename: Bernhard
authors.initials: B
authors.lastname: Blümich
authors.forename: Stephan
authors.initials: S
authors.lastname: Appelt