Moscovium-290

Properties and data of the isotope ²⁹⁰Mc.

Contents

General Data

Radioactive Decay

Parent Nuclides

Isotones und Isobares

Literature

Moscovium-290 is a radioisotope of the chemical element Moscovium, which, in addition to the element-specific 115 protons, has 175 neutrons in the atomic nucleus, resulting in the mass number 290. The very short-lived radioactive nuclide has no practical significance; dealing with ²⁹⁰Mc is for academic purposes only.

²⁹⁰Mc was identified as a direct decay product of the artificially generated nuclide tennessine-294 observed; synthetic production has not yet succeeded. At 650 milliseconds, the nuclide ²⁹⁰Mc has the longest known half-life of any Mc isotope [1]. Accordingly, the atomic weight of the element is given as [290].

The first observation of the isotope ²⁹⁰Mc was reported in a publication from 2010. In the experiment described there, a berkelium-249 target was irradiated with a 252-MeV calcium-48 beam, producing the parent isotope tennessine-294 through the reaction ²⁴⁹Bk(⁴⁸Ca,3n)²⁹⁴Ts [1]. ²⁹⁰Mc was subsequently identified via α decay within the observed decay chain [1].

In a later report, additional information on the same reaction was published, confirming that moscovium-290 appears as an α-decaying member of the decay sequence originating from ²⁹⁴Ts [2].

The small number of recorded events results in an experimental data basis that remains weakly constrained.

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

General data

Name of the isotope:Moscovium-290; Mc-290Symbol:²⁹⁰Mc or 290115McMass number A:290 (= number of nucleons)Atomic number Z:115 (= number of protons)Neutrons N:175Nucleon pairing (Z - N):odd - oddNuclear ratio (N/Z ratio):1.5217391304348 (= neutron-proton ratio)Neutron excess (N-Z):60Isotopic mass:290.19624(64) u (atomic weight of Moscovium-290)Nuclide mass:290.1331645 u (calculated nuclear mass without electrons)Mass excess:182.79638 MeVMass defect:2.21999898 u (per nucleus)Nuclear binding energy:2067.91572988 MeV (per nucleus)
7.1307439 MeV (average binding energy per nucleon)Separation energy:S_N = 5.963(976) MeV (first neutron)
S_P = 1.963(782) MeV (first proton)Half-life:0.65(+0.49-0.20) sDecay constant λ:1.0663802777845 s^-1Specific activity α:2.21444560106 × 10⁺²¹ Bq g^-1
59849881109.757 Ci g^-1Spin and parity:
(nuclear angular momentum)Year of discovery:2010

Radioactive Decay

Half-life T_½ = 0.65(+0.49-0.20) s respectively 6.5 × 10^-1 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
α	²⁸⁶Nh	< 100 %	10.410(40) MeV

Production and radioactive decay chain of moscovium-290

Parent Nuclides

Direct parent isotope is: ²⁹⁴Ts.

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 175) and isobaric (same nucleon number A = 290) with Moscovium-290. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 175	Isobar A = 290
111	²⁸⁶Rg
114	²⁸⁹Fl	²⁹⁰Fl
115	²⁹⁰Mc	²⁹⁰Mc
116	²⁹¹Lv	²⁹⁰Lv

Literature and References

[1] - Yu. Ts. Oganessian et al.:
Synthesis of a New Element with Atomic Number Z=117.
In: Physical Review Letters, 104, 142502, (2010), DOI 10.1103/PhysRevLett.104.142502.

[2] - J. Khuyagbaatar et al.:
Fusion reaction ⁴⁸Ca + ²⁴⁹Bk leading to formation of the element Ts (z=117).
In: Physical Review C, 99, 054306, (2019), DOI 10.1103/PhysRevC.99.054306.