David Lyndon Emsley FRSC (born 29 November 1964) is a British chemist specialising in solid-state nuclear magnetic resonance and a professor at EPFL (École Polytechnique Fédérale de Lausanne).

In 1993 he moved to the French National Laboratory for Atomic Energy Research in Grenoble, where he worked as a post-doc with Claude Roby and Michel Bardet.

[10] In 2003 Emsley was appointed as project leader for the creation in Villeurbanne of the Centre Européen de Résonance Magnétique Nucléaire à Très Hauts Champs (CRMN, European Laboratory for Very High Field NMR), which was the first step in launching the forthcoming Institute of Analytical Sciences (ISA).

[10] In June 2014 he moved to the EPFL as a professor of Physical Chemistry,[12] where he is currently director of the Laboratoire de résonance magnétique of the ISIC (Institute of chemical sciences and engineering).

[7][20] CRMN was also one of the first laboratories in the world to install a high field (800 MHz proton resonant frequency) solid state DNP accessory[21] and to test the new very fast 0.7 mm MAS rotors.

[28] In 2009 Emsley's group showed the possibility of total structure determination of drug-sized organic molecules through the combination of density functional theory and solid-state NMR.

[31] Through DNP, transfer of polarization and relevant signal enhancement can occur from the protons of the solvent batch to the rarer nuclei at natural isotopic abundance on the surface framework, including species covalently bonded to the latter one.

The CRMN was one of the groups developing tools and protocols for the structural and dynamic characterization of proteins in solid phase, including preparations of micro-crystalline samples, role of solvent,[35] paramagnetic systems and sequential assignment,[36] with a progressive introduction thanks to ultra-fast MAS of direct proton acquisition mimicking the sequences used for liquid NMR spectra.

[37] In collaboration with Martin Blackledge his team published some of the first ssNMR methods for the characterization of atom-specific dynamics in biosolids and its relation with solvent behaviour and function, providing detailed insight about the hierarchy of motions in proteins with the increase of temperature.