Boron-18

Properties and data of the isotope ¹⁸B.

Content

General data

Name of the isotope:Boron-18; B-18Symbol:¹⁸B or 185BMass number A:18 (= number of nucleons)Atomic number Z:5 (= number of protons)Neutrons N:13Isotopic mass:18.05560(22) u (atomic weight of Boron-18)Nuclide mass:18.0528571 u (calculated nuclear mass without electrons)Mass excess:51.79107 MeVMass defect:0.096169068000002 u (per nucleus)Nuclear binding energy:89.58090983 MeV (per nucleus)
4.97671721 MeV (average binding energy per nucleon)Half-life:< 26 nsDecay constant λ:26659506.944613 s^-1Specific activity α:8.919294782051 × 10⁺²⁹ Bq g^-1
2.410620211365 × 10⁺¹⁹ Ci g^-1Spin and parity:
(nuclear angular momentum)(2-)

Radioactive Decay

Half-life T_½ = < 26 ns respectively 2.6 × 10^-8 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
n	¹⁷B

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 13) and isobaric (same nucleon number A = 18) with Boron-18. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 13	Isobar A = 18
5	¹⁸B	¹⁸B
6	¹⁹C	¹⁸C
7	²⁰N	¹⁸N
8	²¹O	¹⁸O
9	²²F	¹⁸F
10	²³Ne	¹⁸Ne
11	²⁴Na	¹⁸Na
12	²⁵Mg
13	²⁶Al
14	²⁷Si
15	²⁸P
16	²⁹S
17	³⁰Cl
18	³¹Ar
19	³²K