โ–ธโ–ธ
  • ๐Ÿ‡ฌ๐Ÿ‡ง Boron
  • ๐Ÿ‡บ๐Ÿ‡ฆ ะ‘ะพั€
  • ๐Ÿ‡จ๐Ÿ‡ณ ็กผ
  • ๐Ÿ‡ณ๐Ÿ‡ฑ Boor
  • ๐Ÿ‡ซ๐Ÿ‡ท Bore
  • ๐Ÿ‡ฉ๐Ÿ‡ช Bor
  • ๐Ÿ‡ฎ๐Ÿ‡ฑ ื‘ื•ืจ
  • ๐Ÿ‡ฎ๐Ÿ‡น Boro
  • ๐Ÿ‡ฏ๐Ÿ‡ต ใƒ›ใ‚ฆ็ด 
  • ๐Ÿ‡ต๐Ÿ‡น Boro
  • ๐Ÿ‡ช๐Ÿ‡ธ Boro
  • ๐Ÿ‡ธ๐Ÿ‡ช Bor
  • ๐Ÿ‡ท๐Ÿ‡บ ะ‘ะพั€

Both isotopes of Boron, B-10 and B-11, are used extensively in the nuclear industry. B-10 is used in the form of boric acid as a chemical shim in pressurized water reactors while in the form of sodium pentaborate it is used for standby liquid control systems in boiling water reactors. B-11 can be used as a neutron reflector. Outside the nuclear industry both isotopes are used as food label to study boron metabolism. B-10 is also used in so-called boron neutron capture therapy (BNCT). Both B-10 and B-11 can be used for the production of two radioisotopes: C-11 and N-13.

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 boron are listed (including any which occur naturally) below.
Isotope Mass / Da Natural abundance (atom %) Nuclear spin (I) Magnetic moment (μ/μN)
10B 10.012 937 0(4) 19.9 (7) 3 1.80065
11B 11.009 305 5(5) 80.1 (7) 3/2 2.688637
Isotope abundances of boron
Isotope abundances of boron. 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 boron are listed above. This table gives information about some radiosotopes of boron, 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
8B 8.024607 0.770 s EC to 8Be; EC + α to 4He; EC + 2 α to n 2 1.0355
9B 9.013329 8 x 10-19 s 2α to 1H; p to 8Be 3/2 1.8006
12B 12.014352 0.0202 s β- to 12C; β- + 3α to n 1 1.0031
13B 13.017780 0.0174 s β- to 13C 3/2 3.17778

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 boron

Common reference compound: BF3.OEt2/CDCl3.

Table of NMR-active nucleus propeties of boron
  Isotope 1 Isotope 2 Isotope 3
Isotope 10B 11B
Natural abundance /% 19.9 80.1
Spin (I) 3 3/2
Frequency relative to 1H = 100 (MHz) 10.743658 32.083974
Receptivity, DP, relative to 1H = 1.00 0.00395 0.132
Receptivity, DC, relative to 13C = 1.00 23.2 777
Magnetogyric ratio, γ (107 rad T‑1 s-1) 2.8746786 8.5847044
Magnetic moment, μ (μN) 2.0792055 3.4710308
Nuclear quadrupole moment, Q/millibarn 84.59(24) 40.59(10)
Line width factor, 1056 l (m4) 14 22

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.