Iridium-187m1

Properties and data of the isotope ^187m1Ir.

Contents

See also: List of individual Iridium isotopes (and general data sources).

General data

Name of the isotope:Iridium-187m1; Ir-187m1Symbol:^187m1Ir or 187m177IrMass number A:187 (= number of nucleons)Atomic number Z:77 (= number of protons)Neutrons N:110Nucleon pairing (Z - N):odd - evenNuclear ratio (N/Z ratio):1.4285714285714 (= neutron-proton ratio)Neutron excess (N-Z):33Excitation energy:186.16(4) keVIsotopic mass:186.95754(3) u (atomic weight of Iridium-187m1)Nuclide mass:186.9153038 u (calculated nuclear mass without electrons)Mass excess:-39.55124 MeVMass defect:1.598128224 u (per nucleus)Nuclear binding energy:1488.64685189 MeV (per nucleus)
7.96067835 MeV (average binding energy per nucleon)Half-life:30.3(6) msDecay constant λ:22.876144572935 s^-1Specific activity α:7.406632524220 × 10⁺²² Bq g^-1
2001792574113.6 Ci g^-1Spin and parity:
(nuclear angular momentum)9/2-

Radioactive Decay

Half-life T_½ = 30.3(6) ms respectively 3.03 × 10^-2 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
Iso	¹⁸⁷Ir	100 %

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
¹⁸⁷Ir		10.5(3) h	3/2+
^187m2Ir	433.75(6) keV	152(12) ns	11/2-

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 110) and isobaric (same nucleon number A = 187) with Iridium-187m1. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 110	Isobar A = 187
69	¹⁷⁹Tm
70	¹⁸⁰Yb
71	¹⁸¹Lu	¹⁸⁷Lu
72	¹⁸²Hf	¹⁸⁷Hf
73	¹⁸³Ta	¹⁸⁷Ta
74	¹⁸⁴W	¹⁸⁷W
75	¹⁸⁵Re	¹⁸⁷Re
76	¹⁸⁶Os	¹⁸⁷Os
77	¹⁸⁷Ir	¹⁸⁷Ir
78	¹⁸⁸Pt	¹⁸⁷Pt
79	¹⁸⁹Au	¹⁸⁷Au
80	¹⁹⁰Hg	¹⁸⁷Hg
81	¹⁹¹Tl	¹⁸⁷Tl
82	¹⁹²Pb	¹⁸⁷Pb
83	¹⁹³Bi	¹⁸⁷Bi
84	¹⁹⁴Po	¹⁸⁷Po
85	¹⁹⁵At
86	¹⁹⁶Rn