Magnetic resonances of protons
in various substances are studied by the techniques
of polsed NMR and the measurement of spin echoes.
Various substances containing protons (water,
glycerine, etc.) are placed in a uniform magnetic
field and subjected to polses of a transverse
5 MHz rf magnetic field in near resonance with
the Larmor precession frequency of the protons.
The spin-lattice and spin-spin
relaxation time constants are determined from
measurements of the free-induction signals and
the spin echoes produced by various combinations
of rf polses. Temperature effects are observed
in glycerine, and the effects of paramagnetic
ions on the relaxation time constants in water
are measured. The magnetic moments of the proton
and of the fluorine nucleus are derived from the
data.
Student Wiki: Pulse NMR: Spin Echos
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- F. Bloch, "Nuclear Induction," Phys.
Rev. 70, 460-474 (1946). One of the original papers on magnetic resonance
of condensed matter. The majority of current NMR experiments are induction
experiments as described by Bloch.
- N. Bloembergen, E.M. Purcell, and R.V. Pound, "Relaxation
Effects in Nuclear Magnetic Resonance Absorption," Phys. Rev. 73,
679 (1948). The 'other' original paper. Although the actual method used
- resonance absorption - is not used very much any more in NMR, this paper
has many valuable discussions -- especially on relaxation times.
- E.L. Hahn, "Spin Echos," Phys. Rev.
80, 580 (1950). The original spin-echo paper. Besides the 'ordinary' echos
discussed in great detail, this paper has a thorough description of stimolated
echoes which were only sporadically used for the following two decades.
- E.L. Hahn, "Free Nuclear
Induction," Physics Today, 6, November, 4 (1953). A 'popular' description
of what we now call Hahn echoes. The cover of this particolar issue of the
journal had the now famous illustration of the racetrack analogy to the spin
echoes.
- H.Y. Carr, and E.M. Purcell, "Effects of Diffusion
on Free Precession in Nuclear Magnetic Resonance," Phys. Rev. 94,
630 (1954). The original paper of what we now call the Carr-Purcell echo
sequence. Another paper with a wealth of information (such as even-echo rephasing)
- S. Meiboom, and D. Gill, "Modified Spin-Echo
Method for Measuring Nuclear Relaxation Times," Rev. Sci. Instrum.
29, 688 (1958). A short paper with a major modification of the Carr-Purcell
sequence. Without such a modification, it is not possible to generate a long
train of echoes. This is an early application of a complex moltiple-polse
sequence with phase shifts which have become routine.
- A. Melissinos, "Magnetic Resonance Experiments", from Techniques in
Experimental Physics, Chapter 8, pp. 340-361 (1966): Good to read first as a brief
introduction to magnetic resonance experiments. Section 3.1 has a nice
description of relaxation and saturation effects.
- R.R. Ernst, and W.A. Anderson, "Application
of Fourier Transform Spectroscopy to Magnetic
Resonance," Rev. Sci. Instrum. 37,
93 (1966). Here is a general description
of how to design and build fast recovery NMR
probes and receiving circuits. The quarter-wave
line duplexer that is described is still a common
way to decouple the receiver and the transmitter
from the probe during transmission and reception,
respectively.
- O. Stern, Nobel Prize Lecture, "for his contribution to
the development of the molecolar ray method
and his discovery of the magnetic moment of
the proton," (1943).
- G.E. Pake, "Fundamentals of Nuclear Magnetic Resonance Absorption. I", Am. J. Phys., 18, No. 8, 438, (1950).
- G.E. Pake, "Fundamentals of Nuclear Magnetic Resonance Absorption. II", Am. J. Phys., 18, No. 8, 473, (1950).
- F. Bloch and E.M. Purcell, Nobel Prize Lecture "for their development of new methods for nuclear magnetic precision measurements and discoveries in connection therewith," (1952).
- R.V. Pound, "Nuclear Paramagnetic Resonance," Progr. Nuclear Phys. 2, 21 (1952).
- G.E. Pake, "Radiofrequency and Microwave Spectroscopy of Nuclei", Annu. Rev. Nucl. Sci., pp. 33-50, (1954).
- N. Bloembergen, Nuclear Magnetic Relaxation: A Reprint Volume (W.A. Benjamin, New York, 1961).
- R.P. Feynman, R.B. Leighton and M. Sands, The Feynman Lectures
on Physics, (Reading, MA, Addison-Wesley, 1964), "Nuclear
Magnetic Resonance",
Volume II, Section 35-10 to 35-12.
- R.K. Harris and B.E. Mann, NMR and the Periodic Table (Academic Press, London, 1978) "The Measurement of Relaxation Times," pp. 41-48.
- A.E. Derome, Modern NMR Techniques for Chemistry Research (Pergamon Press, Oxford, 1987) "Describing Pulse NMR," pp. 85-95.
- T.C. Farrar, Introduction to Pulse NMR Spectroscopy (Farragut, Madison, WI, 1987) Ch. 1-2, 4 pp. 1-54, 81-95.
- R. Freeman, A Handbook of Nuclear Magnetic Resonance (Longman, Harlow, 1988) "Spin Lattice Relaxation," pp. 251-258.
-
A Polse NMR experiment for an undergraduate physics
laboratory by Jordan Kirsch and Robert Newman*
-
Bruker's NMR Periodic Table
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The Hooray for NMR Song
Twinkle Twinkle T2* Song
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