Flerovium-285

Properties and data of the isotope ²⁸⁵Fl.

Content

Flerovium-285 is a radioisotope of the chemical element flerovium, which, in addition to the element-specific 114 protons, has 171 neutrons in the atomic nucleus, resulting in the mass number 285. The very short-lived, only artificially producible, unstable and therefore radioactive nuclide has no practical significance; dealing with ²⁸⁵Fl is for academic purposes only.

General data

Name of the isotope:Flerovium-285; Fl-285Symbol:²⁸⁵Fl or 285114FlMass number A:285 (= number of nucleons)Atomic number Z:114 (= number of protons)Neutrons N:171Isotopic mass:285.18350(43) u (atomic weight of Flerovium-285)Nuclide mass:285.1209729 u (calculated nuclear mass without electrons)Mass excess:170.92915 MeVMass defect:2.190254284 u (per nucleus)Nuclear binding energy:2040.20872402 MeV (per nucleus)
7.1586271 MeV (average binding energy per nucleon)Separation energy:S_N = 5.919(770) MeV (first neutron)
S_P = 2.948(669) MeV (first proton)Half-life:0.101 sDecay constant λ:6.8628433718806 s^-1Specific activity α:1.450140683689 × 10⁺²² Bq g^-1
391929914510.65 Ci g^-1Spin and parity:
(nuclear angular momentum)(3/2+)Year of discovery:2010

Radioactive Decay

Half-life T_½ = 0.101 s respectively 1.01 × 10^-1 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
α	²⁸¹Cn	≥ 87.5 %	10.560(71) MeV
SZ	div	≤ 12.5 %

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 171) and isobaric (same nucleon number A = 285) with Flerovium-285. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.