NMRlab
  • Login & order NMR service now
  • NMR service
    Login & order NMR service now NMR service NMR chromatography service Why use our superior service Contact us The NMR team How to submit samples Use the instruments yourself Terms & conditions
  • (53Cr) Chromium NMR
    (53Cr) Chromium NMR Properties of 53Cr References Safety note
  • NMR
    Go to home page What is NMR Techniques Apps Guides Contact us
  • עברית
  • HU NMR lab
  • Login & order NMR service now
  • NMR service
    Login & order NMR service now NMR service NMR chromatography service Why use our superior service Contact us The NMR team How to submit samples Use the instruments yourself Terms & conditions
  • (53Cr) Chromium NMR
  • Properties of 53Cr
  • References
  • Safety note
  • What is NMR
    What is NMR Uses of NMR Basis of NMR Chemical shift Spin-spin coupling
  • Techniques
    Techniques 1H NMR 2D NMR Relaxation Multinuclear Semi-solids Solid state
  • Apps
    Apps Solvent shifts NMR thermometer Reference frequency
  • Guides
    Guides Measuring a 1H spectrum on the old 500 Measuring a 1H spectrum Measuring other nuclei Measuring 2D NMR Measuring diffusion Measuring relaxation Measuring solid & semi-solid
  • Contact us
  • Terms & conditions
  • עברית

(53Cr) Chromium NMR

53Chromium (53Cr) is the only NMR active nucleus of chromium. It is a low sensitivity nucleus that yields moderately broad lines in symmetric environments (fig. 1) over a very wide chemical shift range. For larger complexes and molecules, the signals become too broad to observe with a high-resolution NMR spectrometer. Even number oxidation states, such as (0) and (VI) of chromium are diamagnetic while odd number oxidation states are paramagnetic yielding signals much too broad to observe with a high-resolution NMR spectrometer. In most cases, a specific oxidation state of chromium is contaminated with other paramagnetic oxidation states so the NMR of 53Cr is restricted to chromates, carbonyls and carbenes. The Cr(II) oxidation state usually contains too much paramagnetic Cr(III) to yield signals in the high-resolution NMR spectrum. Only in the case of (CO)3Cr carbenes have signals been observed on a high-resolution NMR spectrometer. There is little information available about chemical shifts (fig. 2).

Fig. 1. 53Cr-NMR spectrum of Na2CrO4 (1M) in D2O

Chromium spectrum

Fig. 2. Chemical shift ranges for chromium NMR

Chemical shifts of chromium

Properties of 53Cr

(Click here for explanation)

PropertyValue
Spin3/2
Natural abundance9.501%
Chemical shift range1795 ppm, from -1795 to 0
Frequency ratio (Ξ)5.652496%
Reference compoundsat. K2CrO4 in D2O
Linewidth of reference10 Hz
T1 of reference0.029 s
Receptivity rel. to 1H at natural abundance8.63 × 10-5
Receptivity rel. to 1H when enriched9.53 × 10-4
Receptivity rel. to 13C at natural abundance0.507
Receptivity rel. to 13C when enriched5.3
Linewidth parameter300 fm4

References

  • E. Haid, D. Koessler, O. Lutz and W. Schich, J. Magn. Reson., 55, 145 (1983).
  • A. Hafnerm, L. S. Hegedus and K. H. Doetz, Adv. Metal Carbene Chem., 247-349 (1989).

Safety note

Some of the materials mentioned here are very dangerous. Ask a qualified chemist for advice before handling them. Qualified chemists should check the relevant safety literature before handling or giving advice about unfamiliar substances. NMR solvents are toxic and most are flammable. Specifically, chromium compounds, including K2CrO4 are toxic carcinogens: wear gloves. Oxidation states VI and VII including K2CrO4 are corrosive.