Ruthenium-122

Properties and data of the isotope ¹²²Ru.

Content

General data

Name of the isotope:Ruthenium-122; Ru-122Symbol:¹²²Ru or 12244RuMass number A:122 (= number of nucleons)Atomic number Z:44 (= number of protons)Neutrons N:78Isotopic mass:121.95475(54) u (atomic weight of Ruthenium-122)Nuclide mass:121.9306137 u (calculated nuclear mass without electrons)Mass excess:-42.1501 MeVMass defect:1.065414856 u (per nucleus)Nuclear binding energy:992.42754587 MeV (per nucleus)
8.13465202 MeV (average binding energy per nucleon)Separation energy:S_N = 5.17(64) MeV (first neutron)
S_P = 17.66(71) MeV (first proton)Half-life:25(1) msDecay constant λ:27.725887222398 s^-1Specific activity α:1.379910729917 × 10⁺²³ Bq g^-1
3729488459236.2 Ci g^-1Spin and parity:
(nuclear angular momentum)0+Year of discovery:2010

Radioactive Decay

Half-life T_½ = 25(1) ms respectively 2.5 × 10^-2 seconds s.

Decay mode	Daughter	Probability	Decay energy
β^-	¹²²Rh		9.93(58) MeV
β^-, n	¹²¹Rh	?	6.03(80) MeV
β^-, 2n		?

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 78) and isobaric (same nucleon number A = 122) with Ruthenium-122. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 78	Isobar A = 122
43	¹²¹Tc
44	¹²²Ru	¹²²Ru
45	¹²³Rh	¹²²Rh
46	¹²⁴Pd	¹²²Pd
47	¹²⁵Ag	¹²²Ag
48	¹²⁶Cd	¹²²Cd
49	¹²⁷In	¹²²In
50	¹²⁸Sn	¹²²Sn
51	¹²⁹Sb	¹²²Sb
52	¹³⁰Te	¹²²Te
53	¹³¹I	¹²²I
54	¹³²Xe	¹²²Xe
55	¹³³Cs	¹²²Cs
56	¹³⁴Ba	¹²²Ba
57	¹³⁵La	¹²²La
58	¹³⁶Ce	¹²²Ce
59	¹³⁷Pr	¹²²Pr
60	¹³⁸Nd
61	¹³⁹Pm
62	¹⁴⁰Sm
63	¹⁴¹Eu
64	¹⁴²Gd
65	¹⁴³Tb
66	¹⁴⁴Dy
67	¹⁴⁵Ho
68	¹⁴⁶Er
69	¹⁴⁷Tm
70	¹⁴⁸Yb
71	¹⁴⁹Lu