Radium-212m1

Properties and data of the isotope ²¹²Ra.

Content

General data

Name of the isotope:Radium-212m1; Ra-212m1Symbol:²¹²Ra or 21288RaMass number A:212 (= number of nucleons)Atomic number Z:88 (= number of protons)Neutrons N:124Isotopic mass:211.999786(12) u (atomic weight of Radium-212m1)
Excitation energy: 1958.4(5) keVNuclide mass:211.951517 u (calculated nuclear mass without electrons)Mass excess:-0.19934 MeVMass defect:1.7632664 u (per nucleus)Nuclear binding energy:1642.472072 MeV (per nucleus)
7.74750977 MeV (average binding energy per nucleon)Half-life:10.9(4) μsDecay constant λ:63591.484455041 s^-1Specific activity α:1.814961501804 × 10⁺²⁶ Bq g^-1
4.905301356228 × 10⁺¹⁵ Ci g^-1Spin and parity:
(nuclear angular momentum)(8)+Magnetic dipole moment:μ(μ_N) = 7.10(7)Nuclear g-factor:g_l = 0.8875

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
²¹²Ra		13.0(2) s	0+
^212m2Ra	2613.4(5) keV	0.85(13) μs	(11)-

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 124) and isobaric (same nucleon number A = 212) with Radium-212m1. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 124	Isobar A = 212
75	¹⁹⁹Re
76	²⁰⁰Os
77	²⁰¹Ir
78	²⁰²Pt
79	²⁰³Au
80	²⁰⁴Hg	²¹²Hg
81	²⁰⁵Tl	²¹²Tl
82	²⁰⁶Pb	²¹²Pb
83	²⁰⁷Bi	²¹²Bi
84	²⁰⁸Po	²¹²Po
85	²⁰⁹At	²¹²At
86	²¹⁰Rn	²¹²Rn
87	²¹¹Fr	²¹²Fr
88	²¹²Ra	²¹²Ra
89	²¹³Ac	²¹²Ac
90	²¹⁴Th	²¹²Th
91	²¹⁵Pa	²¹²Pa
92	²¹⁶U