Tin-131

Properties and data of the isotope ¹³¹Sn.

Content

General data

Name of the isotope:Tin-131; Sn-131Symbol:¹³¹Sn or 13150SnMass number A:131 (= number of nucleons)Atomic number Z:50 (= number of protons)Neutrons N:81Isotopic mass:130.917053(4) u (atomic weight of Tin-131)Nuclide mass:130.8896256 u (calculated nuclear mass without electrons)Mass excess:-77.26463 MeVMass defect:1.176056796 u (per nucleus)Nuclear binding energy:1095.48984913 MeV (per nucleus)
8.36251793 MeV (average binding energy per nucleon)Separation energy:S_N = 5.204(4) MeV (first neutron)
S_P = 14.67(4) MeV (first proton)Half-life:56.0(5) sDecay constant λ:0.012377628224285 s^-1Specific activity α:5.733832359890 × 10⁺¹⁹ Bq g^-1
1549684421.5919 Ci g^-1Spin and parity:
(nuclear angular momentum)(3/2+)Magnetic dipole moment:μ(μ_N) = + 0.746(4)Quadrupole moment Q:- 0.04 barn (100 fm²)Nuclear g-factor:g_l = 0.49733333333333Charge radius:4.7078(73) femtometer fmYear of discovery:1963

Radioactive Decay

Half-life T_½ = 56.0(5) s respectively 5.60 × 10¹ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	¹³¹Sb	100 %	4.717(4) MeV

Parent Nuclides

Direct parent isotopes are: ¹³¹In, ¹³²In, ²⁴⁸Cm.

Nuclear Isomers

Nuclear isomers or excited states with the activation energy in keV related to the ground state.

Nuclear Isomer	Excitation Energy	Half-life	Spin
^131mSn	+x keV	58.4(5) s	(11/2-)

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 81) and isobaric (same nucleon number A = 131) with Tin-131. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 81	Isobar A = 131
45	¹²⁶Rh
46	¹²⁷Pd
47	¹²⁸Ag	¹³¹Ag
48	¹²⁹Cd	¹³¹Cd
49	¹³⁰In	¹³¹In
50	¹³¹Sn	¹³¹Sn
51	¹³²Sb	¹³¹Sb
52	¹³³Te	¹³¹Te
53	¹³⁴I	¹³¹I
54	¹³⁵Xe	¹³¹Xe
55	¹³⁶Cs	¹³¹Cs
56	¹³⁷Ba	¹³¹Ba
57	¹³⁸La	¹³¹La
58	¹³⁹Ce	¹³¹Ce
59	¹⁴⁰Pr	¹³¹Pr
60	¹⁴¹Nd	¹³¹Nd
61	¹⁴²Pm	¹³¹Pm
62	¹⁴³Sm	¹³¹Sm
63	¹⁴⁴Eu	¹³¹Eu
64	¹⁴⁵Gd
65	¹⁴⁶Tb
66	¹⁴⁷Dy
67	¹⁴⁸Ho
68	¹⁴⁹Er
69	¹⁵⁰Tm
70	¹⁵¹Yb
71	¹⁵²Lu
72	¹⁵³Hf