โ–ธโ–ธ
  • ๐Ÿ‡ฌ๐Ÿ‡ง Carbon
  • ๐Ÿ‡บ๐Ÿ‡ฆ ะ’ัƒะณะปะตั†ัŒ
  • ๐Ÿ‡จ๐Ÿ‡ณ ็ขณ
  • ๐Ÿ‡ณ๐Ÿ‡ฑ Koolstof
  • ๐Ÿ‡ซ๐Ÿ‡ท Carbone
  • ๐Ÿ‡ฉ๐Ÿ‡ช Kohlenstoff
  • ๐Ÿ‡ฎ๐Ÿ‡ฑ ืคื—ืžืŸ
  • ๐Ÿ‡ฎ๐Ÿ‡น Carbonio
  • ๐Ÿ‡ฏ๐Ÿ‡ต ็‚ญ็ด 
  • ๐Ÿ‡ต๐Ÿ‡น Carbono
  • ๐Ÿ‡ช๐Ÿ‡ธ Carbono
  • ๐Ÿ‡ธ๐Ÿ‡ช Kol
  • ๐Ÿ‡ท๐Ÿ‡บ ะฃะณะปะตั€ะพะด

Carbon isotopes and mainly C-13 is used extensively in many different applications. C-13 is used for instance in organic chemistry research, studies into molecular structures, metabolism, food labeling, air pollution and climate change. C-13 is also used in breath tests to determine the presence of the helicobacter pylori bacteria which causes stomach ulcer. C-13 can also be used for the production of the radioisotope N-13 which is a PET isotope. The C-12 atom has been given the atomic weight of exactly 12.000000000 and is used as the basis upon which the atomic weight of other isotopes is determined.

Naturally occurring isotopes

This table shows information about naturally occuring isotopes, their atomic masses, their natural abundances, their nuclear spins, and their magnetic moments. Further data for radioisotopes (radioactive isotopes) of carbon are listed (including any which occur naturally) below.
Isotope Mass / Da Natural abundance (atom %) Nuclear spin (I) Magnetic moment (μ/μN)
12C 12.000 000 0(0)* 98.93 (8) 0 0
13C 13.003 354 8378(10) 1.07 (8) 1/2 0.702411
Isotope abundances of carbon
Isotope abundances of carbon. In the above, the most intense ion is set to 100% since this corresponds best to the output from a mass spectrometer. This is not to be confused with the relative percentage isotope abundances which totals 100% for all the naturally occurring isotopes.

Radiosotope data

Further data for naturally occuring isotopes of carbon are listed above. This table gives information about some radiosotopes of carbon, their masses, their half-lives, their modes of decay, their nuclear spins, and their nuclear magnetic moments.
Isotope Mass / Da Half-life Mode of decay Nuclear spin Nuclear magnetic moment
9C 9.031040 0.127 s EC to 9B; EC + p to 8Be; EC + 2α to 2H 3/2
10C 10.016853 19.3 s EC to 10B 0
11C 11.011433 20.3 m EC to 11B 3/2 -0.964
14C 14.003241982 (27) 5715 y β- to 14N 0
15C 15.010599 2.45 s β- to 15N 1/2 1.32
16C 16.014701 0.75 s β- to 16N
17C 17.02258 0.19 s β- to 17N; β- + n to 16N

References

  1. Naturally occurring isotope abundances: Commission on Atomic Weights and Isotopic Abundances report for the International Union of Pure and Applied Chemistry in Isotopic Compositions of the Elements 1989, Pure and Applied Chemistry, 1998, 70, 217. [Copyright 1998 IUPAC]
  2. For further information about radioisotopes see Jonghwa Chang's (Korea Atomic Energy Research Institute) Table of the Nuclides
  3. Masses, nuclear spins, and magnetic moments: I. Mills, T. Cvitas, K. Homann, N. Kallay, and K. Kuchitsu in Quantities, Units and Symbols in Physical Chemistry, Blackwell Scientific Publications, Oxford, UK, 1988. [Copyright 1988 IUPAC]

NMR Properties of carbon

Common reference compound: Si(CH3)4/CDCl3 (1%).

Table of NMR-active nucleus propeties of carbon
  Isotope 1 Isotope 2 Isotope 3
Isotope 11C 13C
Natural abundance /% 1.07
Spin (I) 1/2
Frequency relative to 1H = 100 (MHz) 25.145020
Receptivity, DP, relative to 1H = 1.00 0.000170
Receptivity, DC, relative to 13C = 1.00 1.00
Magnetogyric ratio, γ (107 rad T‑1 s-1) 6.728284
Magnetic moment, μ (μN) 1.216613
Nuclear quadrupole moment, Q/millibarn 33.27(24) -
Line width factor, 1056 l (m4) -

References

  1. R.K. Harris in Encyclopedia of Nuclear Magnetic Resonance, D.M. Granty and R.K. Harris, (eds.), vol. 5, John Wiley & Sons, Chichester, UK, 1996. I am grateful to Professor Robin Harris (University of Durham, UK) who provided much of the NMR data, which are copyright 1996 IUPAC, adapted from his contribution contained within this reference.
  2. J. Mason in Multinuclear NMR, Plenum Press, New York, USA, 1987. Where given, data for certain radioactive nuclei are from this reference.
  3. P. Pyykkö, Mol. Phys., 2008, 106, 1965-1974.
  4. P. Pyykkö, Mol. Phys., 2001, 99, 1617-1629.
  5. P. Pyykkö, Z. Naturforsch., 1992, 47a, 189. I am grateful to Professor Pekka Pyykkö (University of Helsinki, Finland) who provided the nuclear quadrupole moment data in this and the following two references.
  6. D.R. Lide, (ed.), CRC Handbook of Chemistry and Physics 1999-2000 : A Ready-Reference Book of Chemical and Physical Data (CRC Handbook of Chemistry and Physics, CRC Press, Boca Raton, Florida, USA, 79th edition, 1998.
  7. P. Pyykkö, personal communication, 1998, 204, 2008, 2010.