Isotopes of bohrium

Bohrium (Bh) has no stable isotopes. A standard atomic mass cannot be given, though the atomic mass of the most stable isotope is approx. 264.12.

Table

nuclide symbol	Z(p)	N(n)	isotopic mass (u)	half-life	nuclear spin	representative isotopic composition (mole fraction)	range of natural variation (mole fraction)
	excitation energy
260Bh	107	153	260.12197(62)#	0.3# ms
261Bh	107	154	261.12166(25)#	13(4) ms [12(+5-3) ms]
262Bh	107	155	262.12289(37)#	290(160) ms
262mBh	300(60) keV			14(4) ms
263Bh	107	156	263.12304(39)#	200# ms
264Bh	107	157	264.1246(3)#	1.3(5) s [0.44(+60-16) s]
265Bh	107	158	265.12515(41)#	0.9(+7-3) s
266Bh	107	159	266.12694(22)#	5(3) s
267Bh	107	160	267.12765(28)#	22(10) s [17(+14-6) s]
268Bh	107	161	268.12976(41)#	25# s
269Bh	107	162	269.13069(44)#	25# s
270Bh	107	163	270.13362(50)#	30# s
271Bh	107	164	271.13518(60)#	40# s
272Bh	107	165	272.13803(65)#	10(+12-4) s
273Bh	107	166	273.13962(89)#	90# min
274Bh	107	167	274.14244(84)#	90# min
275Bh	107	168	275.14425(70)#	40# min

Notes

• Values marked # are not purely derived from experimental data, but at least partly from systematic trends. Spins with weak assignment arguments are enclosed in parentheses.
• Uncertainties are given in concise form in parentheses after the corresponding last digits. Uncertainty values denote one standard deviation, except isotopic composition and standard atomic mass from IUPAC which use expanded uncertainties.

References

• Isotope masses from Ame2003 Atomic Mass Evaluation by G. Audi, A.H. Wapstra, C. Thibault, J. Blachot and O. Bersillon in Nuclear Physics A729 (2003).
• Isotopic compositions and standard atomic masses from Atomic weights of the elements. Review 2000 (IUPAC Technical Report). Pure Appl. Chem. Vol. 75, No. 6, pp. 683–800, (2003) and Atomic Weights Revised (2005).
• Half-life, spin, and isomer data selected from these sources. Editing notes on this article's talk page.
  • Audi, Bersillon, Blachot, Wapstra. The Nubase2003 evaluation of nuclear and decay properties, Nuc. Phys. A 729, pp. 3–128 (2003).
  • National Nuclear Data Center, Brookhaven National Laboratory. Information extracted from the NuDat 2.1 database (retrieved Sept. 2005).
  • David R. Lide (ed.), Norman E. Holden in CRC Handbook of Chemistry and Physics, 85th Edition, online version. CRC Press. Boca Raton, Florida (2005). Section 11, Table of the Isotopes.