The Russell Varian
Prize
Former Russell Varian
Prize Laureates and Laudatios
Laudatio 2014
Awarded contribution:
A. Bax, A.F. Mehlkopf and J. Smidt,
Homonuclear broadband decoupled absorption spectra, J. Magn.
Reson. 35, 167-169 (1979).
The Prize Winner:
Adriaan Bax NIH Distinguished
Investigator National Institutes of Health, Bethesda, MD, USA
The Technology:
The indirect dimension in multidimensional
NMR spectra allows recording of spectra that cannot be recorded directly in an
FID. Constant-time spectroscopy builds on this idea to observe homonuclear
decoupled spectra, and has found widespread use in modern multidimensional NMR
spectroscopy. In addition to spectral simplification it can also have the added
benefits of sensitivity enhancement and pulse sequence simplification.
Constant-time COSY was the first useful application and nowadays almost all 3D
or 4D liquid-state pulse sequences for biological NMR employ the constant-time
building block.
Laudatio 2013
Awarded Contribution:
L. Frydman, T. Scherf, and A. Lupulescu, The acquisition of multidimensional NMR spectra within a single scan,
Proc. Natl. Acad. Sci. USA, 99, 15858-15862 (2002).
The Prize Winner:
Lucio Frydman, Professor and
Kimmel Fellow, Weizmann Institute, Chemical Physics Department, Israel
The Technology:
The paper, based on an original idea
conceived by Lucio Frydman,
the inspiration behind the contribution of the three authors, introduces a
novel and unique technique for recording multidimensional NMR spectra in a
single scan, and describes the theoretical basis and experimental realization
of this ultrafast NMR methodology. The methodology is proving to be invaluable
in experiments that capitalize on spin hyperpolarization, and is providing
important insights into fast processes, including chemical reactions,
biochemical pathways, and protein folding, that are inaccessible on the time
scale of conventional multidimensional NMR methods. Frydman's
technique has laid the foundation not only for advances in NMR, but also for a
robust complement to echo planar imaging (EPI), the currently prevailing single
scan methodology for ultrafast MRI, and it has demonstrated the possibility of
producing, in high-field preclinical and clinical settings, previously
inaccessible diffusion-weighted and functional images.
Laudatio 2012
Awarded Contribution:
R. Freeman and W. A. Anderson, Use of
Weak Perturbing Radio-Frequency Fields in Nuclear Magnetic Double Resonance, J.
Chem. Phys. 37, 2053 (1962).
The Prize Winners:
Dr. Ray Freeman and Dr. Weston A. Anderson,
Varian Associates, Instrument Division, Palo Alto, California USA
The Technology:
A theory is developed to explain high‐resolution
nuclear magnetic resonance spectra observed in the presence of a second weak rf field at ω2. When ω2 is set on a nondegenerate transition frequency and the rest of the
spectrum recorded by sweeping the frequency of the investigating rf field, any transitions that have an energy level in
common with the perturbed transition will be split into doublets. If magnetic
field inhomogeneities exceed the natural linewidth, the line profile of the doublets gives
information about the ordering of the three energy levels involved. Good
agreement with the theory has been obtained in experiments on two‐spin
and three‐spin proton systems where the energy‐level diagram is
already known. The method has been used to establish the ordering of the energy
levels of the ABC system of protons in methyltrivinylsilane
and the analysis has been completed by two independent methods. Some of the
special effects which arise when double‐resonance
spectra are recorded by sweeping the magnetic field have been examined
and discussed.
Laudatio 2011
Awarded Contribution:
Gareth A. Morris, and Ray Freeman:
Enhancement of nuclear magnetic resonance signals by polarization transfer , J. Am. Chem. Soc. 101, 760-762 (1979).
The Prize Winner:
Gareth Alun
Morris, Professor of Physical Chemistry, School of Chemistry, The University of
Manchester, UK
The Technology:
INEPT is an ingenious pulse sequence,
originally devised for signal enhancement in liquid state NMR of insensitive
nuclei such as carbon-13 and nitrogen-15, by broadband polarization transfer
from proton spins. Since its inception it has evolved, as a means of
bi-directional polarization transfer between coupled spins, into a major
component of modern multidimensional NMR techniques, with applications in
liquids, liquid crystals and solids. The impact of INEPT, transcending its
remarkably simple theoretical and experimental foundation, has made it an
indispensable component of the state-of-the-art NMR toolkit.
Laudatio 2010
Awarded Contribution:
M. Karplus,
Contact Electron-Spin Coupling of Nuclear Magnetic
Moments , J. Chem. Phys. 30, 11-15 (1959)
Prize Winner:
Martin Karplus,
Professor Emeritus, Department of Chemistry and Chemical Biology, Harvard
University, Cambridge, Massachusetts; and
Laboratoire de Chimie Biophysique, ISIS, UniversitŽ
Louis Pasteur, Strasbourg, France
The Technology:
The paper introduces a theoretical
derivation of the dependence of three-bond J coupling constants on the dihedral
angle and includes preliminary comparisons with experimental values. The
presented equations for J(ϕ) have been refined over the years and have come to be
known as the Karplus equations. They have widely
proven themselves as valid for almost all combinations of magnetic nuclei
separated by three bonds and therefore are, next to the distance measurement by
the Nuclear Overhauser enhancement, the most valuable
parameter for structure elucidation, from small molecules to biological
macromolecules. The importance of 3J couplings as a structural parameter has
triggered the development of a large number of NMR pulse sequences specifically
designed to measure them in various circumstances.
Laudatio 2009
Awarded Contribution:
The talk given by Albert Overhauser
at the American Physical Society meeting on May 1, 1953, of which an abstract
appeared as Albert W. Overhauser, Polarization of
Nuclei in Metals, Phys. Rev. 91, 476 (1953), and full detail as Albert W. Overhauser, Polarization of Nuclei in Metals, Phys. Rev.
92, 411-415 (1953).
Prize Winner:
Albert W. Overhauser,
Stuart Distinguished Professor of Physics, Purdue University, West Lafayette,
IN, US.
The Technology:
This contribution is the seed of two
important techniques in modern NMR: the Nuclear Overhauser
Effect (NOE) and Dynamic Nuclear Polarization (DNP).
NOE describes the mutual influence of the
polarizations of two spin species by spin-lattice relaxation. Originally, the
spins were those of the nuclei of a metal and those of its conduction
electrons. Soon after Overhauser's prediction, the
effect was demonstrated by C. P. Slichter on metallic
lithium, and was shown by Ionel Solomon to also exist
between different nuclei in ordinary liquids. The NOE has played a key role in
liquid state NMR over several decades, notably in establishing the overall
structure of biological macromolecules in solution.
DNP describes the often
impressive enhancement of the nuclear polarization by strong irradiation
of an electron resonance in the sample. Particularly within recent years, DNP
technology has evolved considerably to a powerful sensitivity enhancement method
in a growing variety of NMR applications.
Laudatio 2008
Awarded Contribution:
A.Pines, M. G. Gibby, and J. S.
Waugh, Proton-Enhanced Nuclear Induction Spectroscopy. A Method for High
Resolution NMR of Dilute Spins in Solids , J. Chem.
Phys. 56, 1776-1777 (1972). The technique announced in this short note is
explained in detail in A. Pines, M. G. Gibby, and J.
S. Waugh, Proton-Enhanced NMR of Dilute Spins in Solids ,
J. Chem. Phys. 59, 569-590 (1973). Alex Pines played the leading role in the
published work.
The Prize Winner:
Professor Alexander Pines, Glenn T. Seaborg
Professor of Chemistry, UC Berkeley, and Senior Scientist, Lawrence Berkeley
National Laboratory, Berkeley USA.
The Technology:
The proposal of a new method for sensitive,
high-resolution observation of rare spins (e.g. 13C in natural abundance) in
solids, in the presence of abundant spins (e.g. protons). Relaxation is first
used to polarize the abundant spins, part of this polarization is then
transferred to the rare spins by cross-polarization "in the rotating
frame", and the free induction response of the rare spins is finally
observed under CW irradiation of the abundant spins. This simple method, often
called just "cross polarization", helped launch the modern era of
solid-state NMR in chemistry, materials, and biology, and inspired a wealth of
useful variations, many of which are still among the popular tools of practical
solid state NMR.
Laudatio 2007
Awarded Contribution:
A.G. Redfield, On the Theory of Relaxation Processes , IBM Journal of Research and Development 1, 19-31
(1957). Recent references to this fundamental paper are often given implicitly
by quoting the revised version published by Redfield in Adv. Magn. Reson. 1, 1-32 (1965).
The Prize Winner:
Alfred G. Redfield, Professor Emeritus of
Physics, Biochemistry, and Rosenstiel Basic Medical
Sciences Research Center, Brandeis University, Waltham, Massachusetts, USA
The Technology:
The awarded paper casts the semi-quantitative
predictions of BPP (Bloembergen, Purcell, and Pound, Phys. Rev. 73, 679 (1948))
in the form that became that of modern spin dynamics. Assuming only that the
"thermal bath" executes a stationary random motion and that the spin
system is weakly coupled to the "bath", Redfield derives a kinetic
equation of motion for the complete spin density operator, taking into account
all spin and spin-spin interactions "exactly", without resort to
transition probability arguments. The paper demonstrates a general scheme,
applicable to any NMR situation: solids, liquids or gasses, many spins coupled
in a molecule, classical or quantum mechanical description of the thermal bath,
or persistent irradiation during the experiment. The paper also provides the
first example of the usefulness of the "Liouville
space" or "superoperator" scheme for
the discussion of NMR problems involving relaxation in a non-trivial way. After
more than 50 years, the early work of Redfield is still a basic reference in
the field of relaxation.
Laudatio 2006
Awarded Contribution:
J.S. Waugh, C.H. Wang, L.M. Huber, and R.L. Vold, Multiple-Pulse NMR Experiments ,
J. Chem. Phys. 48, 662-670 (1968). This paper announces further results that
appeared a few weeks later in J. S. Waugh, L. M. Huber, and U. Haeberlen, "Approach to High-Resolution NMR in
Solids", Phys. Rev. Lett. 20, 180-182 (1968).
The Prize Winner:
John S. Waugh, Professor emeritus,
Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
The Technology:
The awarded paper is the seed for
multi-pulse line-narrowing, coherent averaging, and
Average Hamiltonian Theory (AHT) in solid-state NMR spectroscopy. The version
of AHT proposed in the awarded contribution unlocked the whole field of
multiple pulse line narrowing in solid-state NMR by providing an efficient
systematic tool for the analysis, design, and optimization of such schemes.
Almost immediately, the first application of the new idea by Waugh was the
WAHUHA sequence for homonuclear line narrowing in solids, which started the
successful development of high-resolution NMR in solids for chemical and
structural applications (beyond the preliminary results of broader and often
unresolved lines obtained with MAS alone). AHT is the method of choice to
understand or design many solid-state pulse sequences like homo- and
heteronuclear decoupling experiments, often in combination with magic-angle
spinning, dipolar recoupling experiments, and advanced experiments for quadrupolar nuclei. In liquid-state NMR, AHT was essential
for the breakthrough of designing the first coherent multi-pulse decoupling
schemes and TOCSY-type elements.
Laudatio 2005
Awarded Contribution:
Nuclear Magnetic Relaxation, by N.
Bloembergen, E. M. Purcell, and R. V. Pound, Nature, 160, 475-476, (1947).
This paper contains all the essential ideas
and results that were later described in greater detail in Bloembergen's PhD
thesis (Leiden, 1948) and in the "BPP" paper, N. Bloembergen, E. M.
Purcell, and R. V. Pound, Relaxation Effects in Nuclear Magnetic Resonance
Absorption, Phys. Rev. 73, 679-712 (1948). A preliminary report was given by
Bloembergen as a Contributed Paper at the APS meeting in New York in late
January 1947 (N. Bloembergen, R. V. Pound, and E. M. Purcell, The Width of the
Nuclear Magnetic Resonance Absorption in Gases, Liquids, and Solids, Phys. Rev.
71, 466 (1947) ).
The Prize Winner:
Nicolaas Bloembergen, Professor
of optical sciences, University of Arizona, Tucson, Arizona, USA, and Gerhard Gade University Professor Emeritus, Division of Applied
Science and Physics Department, Harvard University, Cambridge, Massachusetts
USA.
The Technology:
The awarded paper proposed a
semi-quantitative prediction for Bloch's relaxation times T1 and T2, based on
an appropriate adaptation of transition probability theory (as originally
presented by Weisskopf and Wigner) combined with the
assumption that relaxation is dominated by the effects of molecular Brownian
motion on a "fluctuating local field" acting on each spin. The paper
introduced the notion of "motional narrowing" and established NMR as
an essential tool for the experimental study of molecular motion, a situation
that still persists today.
Laudatio 2004
Awarded Contribution:
E. L. Hahn, Spin Echoes, Bull. Am. Phys.
Soc. 24, No. 7, 13 (1949), reprinted in Phys. Rev. 77, 746 (1950). (This is the
abstract for a ten minutes presentation to be given at the Chicago meeting of
the American Physical Society on November 25, 1949.)
The Prize Winner:
Erwin L. Hahn, Professor Emeritus,
University of California, Berkeley, USA.
The Technology:
The awarded contribution contains several
original ideas and results that have had a strong impact on modern NMR
technology, notably
- (a) the two pulse
spin echo that still is the method of choice for e.g. refocusing chemical shift
dephasings in pulse sequences, not to mention
widespread applications in MRI;
- (b) the
interpretation of spin echoes, where time (rather than frequency) is used as
the essential variable beyond the initial stage of Bloch's theory of CW
spectroscopy and of relaxation measurements: this spin dynamics method was
immediately essential for the development of spin echo applications, and it is
still today the theoretical approach used for most NMR techniques;
- (c) the experimental
demonstration that the observation of NMR pulse responses is a viable
technology that can provide higher sensitivity than CW spectroscopy.
The awarded contribution clearly was the
foundation for the more extensive description of spin echoes in E. L. Hahn,
Spin Echoes, Phys. Rev. 80, 580-594 (1950), that was submitted six months after
the lecture at the Chicago meeting, where further high-impact ideas related to
spin echoes were presented:
- (d) the study of
molecular diffusion and bulk motion by observation of their effects on the spin
echoes: with minor modifications, this is still the method of choice for
accurate measurements of molecular diffusion coefficients in liquids and for
flow measurements in general;
- (e) the study of
"secondary" spin echoes after three pulses, another step towards
multiple-pulse techniques;
- (f) the
observation of a modulation of the peak spin echo amplitudes in some
homonuclear spin systems and the conclusion that the modulation cannot be
explained by differences in chemical shifts, hence that it indicates a new
spin-spin coupling not averaged out by molecular motion. This proved later to
be J couplings. It also showed that multiple-pulse spectroscopy provides
important qualitative information that was not directly available by CW
techniques;
- (g) the
description and use of a coherent pulse spectrometer including a CW reference
oscillator at the NMR frequency, hence control of the phase of the pulses and
observation of the phase of the spin responses: the basic elements of modern
pulse spectrometers are presented here for the first time.
Laudatio 2002
Awarded Contribution:
The lecture given at the Ampere Summer
School in Basko Polje,
Yugoslavia, September, 1971, where Jean Jeener introduced two-dimensional Fourier NMR spectroscopy
by what is today known as the COSY experiment. The unpublished lecture notes
were later published in NMR and More in Honour of
Anatole Abragam , Eds. M. Goldman and M. Porneuf,
Les editions de physique, Avenue du Hoggar, Zone Industrielle de Courtaboeuf, BP
112, F-91944 Les Ulis cedex
A, France (1994).
The Prize Winner:
Jean Jeener,
Professor Emeritus, Universitâ Libre
de Bruxelles, Belgium.
The Technology:
The awarded contribution introduced
two-dimensional NMR spectroscopy and has shown an unprecedented impact on the
development of state-of-the-art NMR spectroscopy. In principle, any
multiple-dimensional NMR experiment introduced so far relies on the method
proposed by Jean Jeener. Countless examples can be
found in both liquid-state and solid-state NMR, as well as in NMR imaging
applications in medicine, biology and material science.