spacer spacer Go to Kaye and Laby Home spacer
spacer
spacer spacer spacer
spacer
spacer
spacer
spacer spacer

You are here:

spacer

Chapter: 3 Chemistry
    Section: 3.8 Molecular spectroscopy
        SubSection: 3.8.1 Nuclear moments and magnetic resonance

spacer
spacer

spacer

« Previous Section

Next Subsection »

Unless otherwise stated this page contains Version 1.0 content (Read more about versions)

3.8 Molecular spectroscopy

3.8.1 Nuclear moments and magnetic resonance

The table includes all naturally occurring isotopes having non-zero spin (excluding 180Ta). The magnetic moment, μ, is given in units of the nuclear magneton  μn(eh/4πMc). The resonant frequency of an isotope is given by

v = μH/hI

where H is the magnetic field at the nucleus, h is Planck's constant and I is the nuclear spin (in units of h/2π). Since radio frequencies are among the most accurately measurable physical quantities known, nuclear magnetic resonance (nmr) measurements should provide highly accurate values of the nuclear moments. However, it was found that the resonance frequency of a given isotope is dependent on the chemical nature of the compound containing that isotope. This ‘chemical shift’ effect, while limiting the accuracy of nuclear moment measurements, has proved to be a most important tool for the determination of molecular structures (see section 3.8.2).

The values of the nuclear moments given are corrected for diamagnetism, arrived at from considering values obtained by various experimental techniques including nmr, atomic beam resonance, electron spin resonance, optical spectroscopy and electron-nuclear double resonance (ENDOR). For a few nuclei the moment values obtained by two different methods are consistent and when this occurs those values are quoted but when discrepancies exist the nmr values have been listed. See G. H. Fuller J. Phys. Chem. Ref. Data, 1976, 5, 835, for further details.

Nuclear electric quadrupole moments are conveniently written e. Q where e is the charge on the electron and the parameter Q is in units of 10−28 m2 (barns). The quadrupole moment values reported are averages of the values reported in the literature (or derived from these), since some uncertainty attaches to the accuracy of any particular value due to the difficulties in estimating the electric field inhomogeneity at the nucleus arising from its molecular and electronic environment. Only those values marked * contain any correction for polarization shielding effects. Such corrections are difficult to quantify and may amount to 30 per cent of the Q value for some nuclei. Spin nuclei have no quadrupole moment.

The nmr frequency values tabulated are those for an externally applied field of 1 tesla (10 kilogauss).

The sensitivity at constant field, relative to the proton, is calculated from the expression (7.652 x 10−3) × μ3(I + 1)/I2. The term assumes a comparison between an equal number of nuclei, at constant temperature, where the longitudinal and transverse relaxation times are equal (i.e., T1 = T2), and with an ideal induced voltage in the receiver coil at saturation with constant source noise; and thus is an optimum value.

The product of the relative sensitivity and the isotopic natural abundance—also listed, and quoted as a percentage—gives the relative receptivity of the nucleus compared with the proton, and is thus a more useful guide to nuclear response in natural abundance nmr determinations. For example, the relative receptivity of 13C compared with 1H is 0.0159 × 1.108 = 0.0176%.

The chemical reference standards listed in the table are either those universally employed (e.g. (Me4Si) or (H3PO4)) or those frequently used, or in a few instances are the only compound of the nuclide to have been observed by nmr techniques.

Some abbreviations used in the table are aq. for aqueous solution, Et for ethyl, Me for methyl, neat for undiluted compound.

The sign of μ/μn and of Q/10−28 m2 is uncertain for those nuclides for which no sign is given.

The symbol in the nuclide column indicates that the isotope highlighted is radioactive.




Nuclear spins, moments and resonant frequencies

Nuclide

I

μ /μN

  Q/10−28 m2

  v/MHz 

  Relative
 sensitivity

  % Natural
abundance

Chemical shift
reference standard

 

 

    

 

  

        

 

0n

   −1.913 12

   —

29.167   

0.322     

  —

1H

   +2.792 78 

   —

42.575 9

1.000      

  99.985

  Me4Si

2H

1

   +0.857 39

+

0.002 73

  6.535 7

0.009 65 

    0.015

  —

3H

   +2.978 77

 

   —

45.412 9

1.210      

  Me4Si-tritiated

3He

   −2.127 6   

 

   —

32.433 8

0.442      

  1.3 × 10− 4

  —

6Li

1

   +0.822 03

– 

0.000 8

  6.265 5

0.008 50  

  7.42

  Li+aq.

7Li

   +3.256 36 

– 

0.045

16.546 5

0.293      

92.58

  Li+aq.

9Be

   −1.177 45

+

0.052 

 5.982 7

0.013 9    

100      

  Be2+aq.

10B

3

   −1.800 6   

+

0.085*

 4.575 4

0.019 9    

19.58

  Et2O.BF3 or BH4

11B

   +2.688 5   

+

0.041*

13.660 1

0.165      

80.42

  Et2O.BF3 or BH4

13C

   +0.702 4   

 

   —

10.705 4

0.015 9   

     1.108

  Me4Si

14N

1

   +1.403 57

+

0.016

  3.075 6

0.001 01 

99.63

  MeNO2 or NO3

15N

   −0.283 1   

 

   —

  4.315 8

0.001 04 

  0.37

  MeNO2 or NO3

17O

   −1.893 7

0.026*

  5.771 9

0.029 1   

    0.037

  H2O

19F

   +2.627 27

 

   —

40.061 3

0.833      

100      

  CCl3F

21Ne

   −0.661 76

+

0.09

  3.361 1

0.002 50 

     0.257

  —

23Na

   +2.217 40

+

0.10* 

11.262 1

0.082 5   

100      

  Na+aq.

25Mg

   −0.855 4   

+

0.22

  2.605 4

0.002 67 

10.13

  Mg2+ aq.

27Al

   +3.641 3   

+

0.149*

11.094 0

0.206      

100     

  [Al(H2O)6]3+

29Si

   −0.555 26

 

   —

  8.457 8

0.007 84 

    4.70

  Me4Si

31P

   +1.130 5

 

   —

17.235 0

0.066 3   

 100       

  85% H3PO4

33S

   +0.643 5   

0.064 

  3.265 4

0.002 26 

   0.76

  CS2 or SO42−

35Cl

   +0.821 81

0.10*

  4.171 7

0.004 7   

75.53

  Claq.

36Cl

2

   +1.285 3   

0.021*

  4.893 1

0.012 1   

  —

37Cl

   +0.684 07

0.079*

 3.472  

 0.002 71 

24.47

  Claq.

39K

   +0.391 47

+

0.049*

   1.986 4 

5.08 × 10− 4

93.10

  K+ aq.

40K

4

   −1.298 1   

0.061*

  2.470  

0.005 21

       0.011 8

  —

41K

   −0.214 87

+

0.067*

  1.090 3

8.40 × 10− 5

  6.88

  K+ aq.

43Ca

   −1.317 2   

0.2

  2.865 4

0.006 40

     0.145

  Ca2+aq.

45Sc

   +4.755 9   

0.22

10.343 4

0.301     

100      

  Sc(ClO4)3aq.

47Ti

   −0.788 46

+

0.29

  2.399 7

0.002 09

  7.28

  TiF62− /48%HFaq.

49Ti

   −1.104 14

+

0.24

  2.400 4

0.003 76

  5.51

  TiF62− /48%HFaq.

50V

6

   +3.347 0   

 

   —

  4.245 0

0.055 5  

  0.24

  —

51V

   +5.148 5   

0.05

11.192 2

0.382     

99.76

  VOCl3 neat

53Cr

   −0.474 4   

+

0.03

  2.406 3

9.03 × 10− 4

  9.55

  CrO42−

55Mn

   +3.468 0   

+

0.55

10.501 0

0.175    

100      

  KMnO4aq.

57Fe

   +0.090 24

 

   —

  1.375 8

3.37 × 10− 5

  2.19

  Fe(CO)5

59Co

   +4.616 3   

+

0.40

10.072    

0.277      

100      

  [Co(CN)6]3− aq.

61Ni

   −0.749 8   

+

0.16*

  3.804 8

0.003 57 

  1.19

  Ni(CO)4 neat

63Cu

   +2.222 6   

0.211*

11.284 7

0.093 1   

69.09

  [Cu(CN)4]3−

65Cu

   +2.384 9   

0.195*

12.089 0

0.114      

30.91

  [Cu(CN)4]3−

67Zn

   +0.875 6   

+

0.15

  2.661 8

0.002 85 

  4.11

  Zn2 + aq.

69Ga

   +2.016 1   

+

0.178

10.218 8

0.069 1   

60.40

  [Ga(H2O)6]3+

71Ga

   +2.561 7  

+

0.112

12.984 0

0.142      

39.60

  [Ga(H2O)6]3+

73Ge

   −0.879 18

0.18

  1.485 2 

0.001 40 

   7.76

  GeCl4 neat

75As

   +1.439     

+

0.29

  7.291 9

0.025 1   

100     

  KAsF6

77Se

   +0.532 5

 

   —

  8.128 4

0.006 93

  7.58

  Me2Se

79Br

   +2.105 5

+

0.37* 

   10.667 0   

0.078 6 

50.54

  Braq.

81Br

   +2.269 6

+

0.31* 

   11.498 0   

0.098 5 

49.46

  Braq.

83Kr

   −0.970 3

+

0.26

  1.638 3

  0.001 88 

11.55

  —

85Rb

   +1.352 7

+

0.26*

 4.110 8

0.010 5 

72.15

  Rb+aq.

87Rb

   +2.750 6

+

0.13*

  13.931 3   

0.175    

27.85

  Rb+aq.

87Sr

   −1.093   

+

0.36

  1.845 1

0.026 9 

  7.02

  Sr2+aq.

89Y

   −0.137 33

 

   —

  2.086 0

 1.18 × 10− 4

100      

  Y(NO3)3aq.

91Zr

   −1.302 84

 

   —

  3.972 5

  0.009 48

11.23

  —

93Nb

   +6.167    

0.22

   10.406 8   

 0.482     

100      

  NbF6/48%HFaq.

95Mo

   −0.913 5

 

0.12

  2.773 8

 0.003 23

15.72

  MoO42−

97Mo

   −0.932 7

 

1.1

  2.832 1

 0.003 43

  9.46

  MoO42−

99Tc

   +5.681    

+

0.3    

 9.583 2

 0.376    

 —

  TcO4 aq.

99Ru

   −0.643 0

 

   —

 1.960 7

1.95 × 10− 4

12.72

  K4[Ru(CN)6]aq.

101Ru

   −0.720 7

 

   —

 2.197 5

  0.001 41

17.07

  —

103Rh

   −0.087 9

 

   —

 1.340 1

3.11 × 10− 5

100      

  mer [RhCl3(SMe2)3]

105Pd

   −0.642    

+

0.8    

 1.892 1

  0.001 12

22.23 

  —

107Ag

   −0.113 5

 

   —

 1.723 0

6.62 × 10− 5

51.82

  —

109Ag

   −0.130 5

 

   —

 1.980 8

1.01 × 10− 4

48.18

  Ag+aq.

111Cd

   −0.595 00

 

   —

 9.028 3

 0.009 54

12.75

  CdMe2 neat

113Cd

   −0.619 50

 

   —

 9.444 1

   0.010 9    

12.26

  CdMe2 neat

113In

   +5.522 9

+

1.14  

 9.310 1

  0.345      

  4.28

  [In(H2O)6]3+

115In

   +5.534 8

+

1.16

 9.330 1

  0.347      

95.72

  —

115Sn

   −0.917 8

 

   —

 13.922     

 0.035 0  

   0.35

  —

117Sn

   −0.999 9

 

   —

 15.168     

 0.045 2  

   7.61 

  —

119Sn

   −1.040 9

 

   —

15.876 8 

 0.051 8  

  8.58

  Me4Sn

121Sb

   +3.359 2

0.28

10.188 4 

 0.160     

57.25

  SbCl6

123Sb

   +2.546 6

0.36

  5.517 6

0.045 7  

42.75

  SbCl6

123Te

   −0.735 9

   —

11.159   

0.018 0  

  0.87

  —

125Te

   −0.882 4

   —

13.453   

0.031 5  

  6.99

  Me2Te

127I

   +2.809 1

0.69

  8.518 3

0.093 4  

100      

  Iaq.

129I

   +2.617 4

0.48

  5.669 4

0.049 6  

 —

  —

129Xe

   −0.772 5

 

   —

  11.776 9  

0.021 2  

26.44

  XeOF4

131Xe

   +0.690 8

0.12

  3.491 1

  0.002 76  

21.18

  —

133Cs

   +2.578 8

0.003 0*

    5.584 69

0.047 4  

100     

  Cs+aq.

135Ba

   +0.837 2

+

0.18

    4.229 5  

  0.004 90  

   6.59

  Ba2+aq.

137Ba

   +0.936 5 

+

0.28

    4.731 4  

  0.006 86  

11.32

  Ba2+aq.

138La

5

   +3.704      

 

0.51*

    5.617 1  

0.091 9  

0.089

  —

139La

   +2.778      

+

0.22* 

    6.014 4  

0.059 2  

99.91

  —

141Pr

   +4.160      

0.058 

   13.0         

0.293     

100     

  —

143Nd 

   −1.063     

0.48

    2.303    

   0.003 38   

12.17

  —

145Nd

   −0.654     

0.25

  1.414  

7.86 × 10− 4

    8.30 

  —

147Sm 

   −0.813    

0.18

   1.72    

  0.001 48  

14.97

  —

149Sm 

   −0.670    

+

0.052

  1.39   

7.47 × 10− 4

13.83

  —

151Eu

   +3.466     

+

1.16

    10.559    

0.178    

47.82

  —

153Eu

   +1.530    

+

2.9

     4.662 7 

 0.015 3  

52.18

  —

155Gd

   −0.258 4

+

1.6

   1.4     

2.79 × 10− 4

14.73

  —

157Gd

   −0.338 8

+

1.7

1.9  

5.44 × 10− 4

15.68

  —

159Tb

   −2.008

+

1.3*

9.66

  0.058 3  

100      

  —

161Dy

   −0.482

+

2.4*

1.39

4.17 × 10− 4

18.88

  —

163Dy

   +0.676

+

2.5*

1.94

  0.001 2  

24.97

  —

165Ho 

   +4.12

+

2.82

8.73

  0.181    

100      

  —

167Er

   -0.569

+

2.83

1.23

5.07 × 10− 4

22.94

  —

169Tm

   −0.230 9

     3.521 9

5.66 × 10− 4

100     

  —

171Yb 

   +0.491 8

     7.498 9

  0.005 46

14.31

  —

173Yb 

   −0.679 1

+

2.8

     2.065 9

  0.001 33

16.13

  —

175Lu 

   +2.230

 +

5.68

     4.818 9

 0.031 2 

97.41

  —

176Lu

7

   +3.180

+

8.0

 3.39

0.037 2

  2.59

  —

177Hf 

   +0.790 2

 +

4.5*

1.3 

6.38 × 10− 4

18.50

  —

179Hf 

   −0.638

+

5.1*

 0.80

2.16 × 10− 4

13.75

  —

181Ta

   +2.35

+

3*

      5.096 3

0.036

    99.988 

  TaF6 in HF/HNO3

183W

   +0.116 9

     1.771 6

7.20 × 10− 5

14.40

  WF6 neat

185Re 

   +3.172

+

2.8

      9.585 5

0.133

37.07

  ReO4aq.

187Re

   +3.204

+

2.6

      9.683 7

0.137

62.93

  ReO4aq.

187Os 

   +0.064 3

        0.980 59

1.22 × 10− 5

  1.64

  OsO4

189Os

   +0.656 5

+

0.8*

      3.303 4

      0.002 34

16.10

  OsO4

191Ir

   +0.145 4

+

1.1

      0.731 8

2.53 × 10− 5

37.30

  —

193Ir

   +0.158 3

+

1.0

      0.796 8

3.27 × 10− 5

62.70

  —

195Pt

   +0.600 4

      9.152 3

    0.009 94

33.80

  [Pt(CN)6]2−

197Au

   +0.144 86

+

0.59

      0.741 2

2.51 × 10− 5

100       

  —

199Hg 

   +0.497 8

    7.612

   0.005 67

16.84

  Me2Hg neat

201Hg 

   −0.558 30

+

0.50

       2.810 0

   0.001 44

13.22

  Me2Hg neat

203Tl

   +1.611 5

   24.332 

    0.187     

29.50

  —

205Tl

   +1.611 6

   24.567 

    0.192     

70.50

  TlNO3aq.

207Pb

   +0.584 3

       8.907 1

    0.009 16

22.60

  Me4Pb

209Bi 

   +4.080 

0.38

         6.841 78

    0.137    

100       

  —

235U 

   −0.43

+

4.9

     0.75  

1.21 × 10− 4

   0.72

  —

             

   




References

(1) G. H. Fuller (1976) J. Phys. Chem. Ref. Data 5, 835.
(2) R. K. Harris and B. E. Mann (eds) (1978) NMR and the Periodic Table, Academic Press.




J.G.E.Phillips

spacer


spacer
spacer
spacer spacer spacer

Home | About | Table of Contents | Advanced Search | Copyright | Feedback | Privacy | ^ Top of Page ^

spacer

This site is hosted and maintained by the National Physical Laboratory © 2017.

spacer