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Isotopes of einsteinium
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<h2 id="list-of-isotopes">List of isotopes</h2> <table><tbody><tr><th rowspan="2">Nuclide<a class="footnote-ref" id="fnref:1" href="#fn:1"><sup>1</sup></a></th><th rowspan="1"><a href="/facts/Atomic_number/bgAr581S"><i>Z</i></a></th><th rowspan="1"><a href="/facts/Neutron_number/eNtwGnVL"><i>N</i></a></th><th rowspan="1"><a href="/facts/Atomic_mass/J1FJY9MV">Isotopic mass</a> (<a href="/facts/Dalton_(unit)/IMATU3vf">Da</a>)<a class="footnote-ref" id="fnref:2" href="#fn:2"><sup>2</sup></a><a class="footnote-ref" id="fnref:3" href="#fn:3"><sup>3</sup></a><a class="footnote-ref" id="fnref:4" href="#fn:4"><sup>4</sup></a></th><th rowspan="2"><a href="/facts/Half-life/kGVH8BAB">Half-life</a><a class="footnote-ref" id="fnref:5" href="#fn:5"><sup>5</sup></a></th><th rowspan="2"><a href="/facts/Decay_mode/Ya6FVjt4">Decaymode</a><a class="footnote-ref" id="fnref:6" href="#fn:6"><sup>6</sup></a><a class="footnote-ref" id="fnref:7" href="#fn:7"><sup>7</sup></a></th><th rowspan="2"><a href="/facts/Decay_product/hT0obfLv">Daughterisotope</a></th><th rowspan="2"><a href="/facts/Spin_(particle_physics)/4Jvp7e8P">Spin</a> and<a href="/facts/Parity_(physics)/emSbJ4hD">parity</a><a class="footnote-ref" id="fnref:8" href="#fn:8"><sup>8</sup></a><a class="footnote-ref" id="fnref:9" href="#fn:9"><sup>9</sup></a><a class="footnote-ref" id="fnref:10" href="#fn:10"><sup>10</sup></a></th></tr><tr><th colspan="3">Excitation energy<a class="footnote-ref" id="fnref:11" href="#fn:11"><sup>11</sup></a></th></tr><tr><td rowspan="3">240Es</td><td rowspan="3">99</td><td rowspan="3">141</td><td rowspan="3">240.06895(39)#</td><td rowspan="3">6.0(17) s</td><td><a href="/facts/Alpha_decay/rCsHNIUE">α</a> (70%)</td><td>236Bk</td><td rowspan="3">4−#</td></tr><tr><td><a href="/facts/Beta_decay/vxTBlckp">β+</a> (30%)</td><td>240Cf</td></tr><tr><td>β+, <a href="/facts/Spontaneous_fission/0QuJoVKI">SF</a> (0.16%)</td><td>(various)</td></tr><tr><td rowspan="2">241Es<a class="footnote-ref" id="fnref:12" href="#fn:12"><sup>12</sup></a></td><td rowspan="2">99</td><td rowspan="2">142</td><td rowspan="2">241.06859(25)#</td><td rowspan="2">4.3+2.4−1.2 s</td><td>α</td><td>237Bk</td><td rowspan="2">3/2−#</td></tr><tr><td>β+?</td><td>241Cf</td></tr><tr><td rowspan="3">242Es<a class="footnote-ref" id="fnref:13" href="#fn:13"><sup>13</sup></a></td><td rowspan="3">99</td><td rowspan="3">143</td><td rowspan="3">242.06957(28)#</td><td rowspan="3">16.9(8) s</td><td>β+</td><td>242Cf</td><td rowspan="3">2+#</td></tr><tr><td>α (41%)</td><td>238Bk</td></tr><tr><td>β+, SF (1.5%)</td><td>(various)</td></tr><tr><td rowspan="2">243Es</td><td rowspan="2">99</td><td rowspan="2">144</td><td rowspan="2">243.06951(22)#</td><td rowspan="2">22.1(14) s</td><td>α (61%)</td><td>239Bk</td><td rowspan="2">(7/2+)</td></tr><tr><td>β+ (39%)</td><td>243Cf</td></tr><tr><td rowspan="3">244Es</td><td rowspan="3">99</td><td rowspan="3">145</td><td rowspan="3">244.07088(20)#</td><td rowspan="3">37(4) s</td><td>β+ (95%)</td><td>244Cf</td><td rowspan="3">6+#</td></tr><tr><td>α (5%)</td><td>240Bk</td></tr><tr><td>β+, SF (0.011%)</td><td>(various)</td></tr><tr><td rowspan="2">245Es</td><td rowspan="2">99</td><td rowspan="2">146</td><td rowspan="2">245.07119(18)#</td><td rowspan="2">1.11(6) min</td><td>β+ (51%)</td><td>245Cf</td><td rowspan="2">(3/2−)</td></tr><tr><td>α (49%)</td><td>241Bk</td></tr><tr><td rowspan="3">245mEs<a class="footnote-ref" id="fnref:14" href="#fn:14"><sup>14</sup></a></td><td rowspan="3" colspan="3">30(15)# keV</td><td rowspan="3">>50# μs</td><td><a href="/facts/Isomeric_transition/L8DHcqnk">IT</a>?</td><td>245Es</td><td rowspan="3">7/2+#</td></tr><tr><td>α?</td><td>241Bk</td></tr><tr><td>β+?</td><td>245Cf</td></tr><tr><td rowspan="3">246Es</td><td rowspan="3">99</td><td rowspan="3">147</td><td rowspan="3">246.072806(97)</td><td rowspan="3">7.5(5) min</td><td>β+ (90.1%)</td><td>246Cf</td><td rowspan="3">4−#</td></tr><tr><td>α (9.9%)</td><td>242Bk</td></tr><tr><td>β+, SF (.003%)</td><td>(various)</td></tr><tr><td rowspan="3">247Es</td><td rowspan="3">99</td><td rowspan="3">148</td><td rowspan="3">247.073622(21)</td><td rowspan="3">4.55(26) min</td><td>β+ (93%)</td><td>247Cf</td><td rowspan="3">(7/2+)</td></tr><tr><td>α (7%)</td><td>243Bk</td></tr><tr><td>SF?</td><td>(various)</td></tr><tr><td rowspan="3">248Es</td><td rowspan="3">99</td><td rowspan="3">149</td><td rowspan="3">248.075469(56)#</td><td rowspan="3">24(3) min</td><td>β+ (99.75%)</td><td>248Cf</td><td rowspan="3">2−#</td></tr><tr><td>α (.25%)</td><td>244Bk</td></tr><tr><td>β+, SF (3.5×10−4%)</td><td>(various)</td></tr><tr><td rowspan="2">249Es</td><td rowspan="2">99</td><td rowspan="2">150</td><td rowspan="2">249.076409(32)#</td><td rowspan="2">102.2(6) min</td><td>β+ (99.43%)</td><td>249Cf</td><td rowspan="2">7/2+</td></tr><tr><td>α (.57%)</td><td>245Bk</td></tr><tr><td rowspan="2">250Es</td><td rowspan="2">99</td><td rowspan="2">151</td><td rowspan="2">250.07861(11)#</td><td rowspan="2">8.6(1) h</td><td>β+</td><td>250Cf</td><td rowspan="2">6(+)</td></tr><tr><td>α?</td><td>246Bk</td></tr><tr><td rowspan="2">250mEs<a class="footnote-ref" id="fnref:15" href="#fn:15"><sup>15</sup></a></td><td rowspan="2" colspan="3">200(150)# keV</td><td rowspan="2">2.22(5) h</td><td>β+</td><td>250Cf</td><td rowspan="2">1(−)</td></tr><tr><td>α?</td><td>246Bk</td></tr><tr><td rowspan="2">251Es</td><td rowspan="2">99</td><td rowspan="2">152</td><td rowspan="2">251.0799914(57)</td><td rowspan="2">33(1) h</td><td><a href="/facts/Electron_capture/EIccoV1u">EC</a> (99.5%)</td><td>251Cf</td><td rowspan="2">3/2−</td></tr><tr><td>α (.5%)</td><td>247Bk</td></tr><tr><td rowspan="2">252Es</td><td rowspan="2">99</td><td rowspan="2">153</td><td rowspan="2">252.082979(54)</td><td rowspan="2">471.7(19) d</td><td>α (78(2)%)</td><td>248Bk</td><td rowspan="2">(4+)</td></tr><tr><td>EC (22(2)%)</td><td>252Cf</td></tr><tr><td rowspan="2">253Es<a class="footnote-ref" id="fnref:16" href="#fn:16"><sup>16</sup></a></td><td rowspan="2">99</td><td rowspan="2">154</td><td rowspan="2">253.0848212(13)</td><td rowspan="2">20.47(3) d</td><td>α</td><td>249Bk</td><td rowspan="2">7/2+</td></tr><tr><td>SF (8.7×10−6%)</td><td>(various)</td></tr><tr><td rowspan="3">254Es</td><td rowspan="3">99</td><td rowspan="3">155</td><td rowspan="3">254.0880243(32)</td><td rowspan="3">275.7(5) d</td><td>α<a class="footnote-ref" id="fnref:17" href="#fn:17"><sup>17</sup></a></td><td>250Bk</td><td rowspan="3">7+</td></tr><tr><td>β− (1.74×10−4%)</td><td>254Fm</td></tr><tr><td>SF (<3×10−6%)</td><td>(various)</td></tr><tr><td rowspan="5">254mEs</td><td rowspan="5" colspan="3">80.4(11) keV</td><td rowspan="5">39.3(2) h</td><td>β− (98(2)%)</td><td>254Fm</td><td rowspan="5">2+</td></tr><tr><td>IT (<3%)</td><td>254Es</td></tr><tr><td>α (0.32(1)%)</td><td>250Bk</td></tr><tr><td>EC (0.076(7)%)</td><td>254Cf</td></tr><tr><td>SF (<0.045%)</td><td>(various)</td></tr><tr><td rowspan="3">255Es</td><td rowspan="3">99</td><td rowspan="3">156</td><td rowspan="3">255.090274(12)</td><td rowspan="3">39.8(12) d</td><td>β− (92.0%)</td><td>255Fm</td><td rowspan="3">(7/2+)</td></tr><tr><td>α (8.0%)</td><td>251Bk</td></tr><tr><td>SF (.0041%)</td><td>(various)</td></tr><tr><td rowspan="2">256Es</td><td rowspan="2">99</td><td rowspan="2">157</td><td rowspan="2">256.09360(11)#</td><td rowspan="2">7.6 h</td><td>β−</td><td>256Fm</td><td rowspan="2">7+#</td></tr><tr><td>β−, SF (.002%)</td><td>(various)</td></tr><tr><td>256mEs<a class="footnote-ref" id="fnref:18" href="#fn:18"><sup>18</sup></a></td><td colspan="3">0(100)# keV</td><td>25.4(12) min</td><td>β−</td><td>256Fm</td><td>0+#</td></tr><tr><td rowspan="2">257Es</td><td rowspan="2">99</td><td rowspan="2">158</td><td rowspan="2">257.09598(44)#</td><td rowspan="2">7.7(2) d</td><td>β−</td><td>257Fm</td><td rowspan="2">7/2+#</td></tr><tr><td>α?</td><td>253Bk</td></tr><tr><th colspan="20"><i>This table header & footer:</i> <ul><li>view</li></ul></th></tr></tbody></table> <ul><li>Isotope masses from: <ul><li>Audi, Georges; Bersillon, Olivier; Blachot, Jean; <a href="/facts/Aaldert_Wapstra/9Ylvt18s">Wapstra, Aaldert Hendrik</a> (2003), <a href="https://hal.archives-ouvertes.fr/in2p3-00020241/document">"The NUBASE evaluation of nuclear and decay properties"</a>, <i>Nuclear Physics A</i>, 729: 3–128, <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/2003NuPhA.729....3A">2003NuPhA.729....3A</a>, <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1016%2Fj.nuclphysa.2003.11.001">10.1016/j.nuclphysa.2003.11.001</a></li></ul></li> <li>Half-life, spin, and isomer data selected from the following sources. <ul><li>Audi, Georges; Bersillon, Olivier; Blachot, Jean; <a href="/facts/Aaldert_Wapstra/9Ylvt18s">Wapstra, Aaldert Hendrik</a> (2003), <a href="https://hal.archives-ouvertes.fr/in2p3-00020241/document">"The NUBASE evaluation of nuclear and decay properties"</a>, <i>Nuclear Physics A</i>, 729: 3–128, <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/2003NuPhA.729....3A">2003NuPhA.729....3A</a>, <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1016%2Fj.nuclphysa.2003.11.001">10.1016/j.nuclphysa.2003.11.001</a></li> <li><a href="/facts/National_Nuclear_Data_Center/SgVzvxLk">National Nuclear Data Center</a>. <a href="http://www.nndc.bnl.gov/nudat2/">"NuDat 2.x database"</a>. <a href="/facts/Brookhaven_National_Laboratory/L2JrG0K1">Brookhaven National Laboratory</a>.</li> <li>Holden, Norman E. (2004). "11. Table of the Isotopes". In Lide, David R. (ed.). <i><a href="/facts/CRC_Handbook_of_Chemistry_and_Physics/qjxzC2Cu">CRC Handbook of Chemistry and Physics</a></i> (85th ed.). <a href="/facts/Boca_Raton,_Florida/9gcNen3S">Boca Raton, Florida</a>: <a href="/facts/CRC_Press/duTuH4hz">CRC Press</a>. <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-0-8493-0485-9.</li></ul></li></ul> <h2 id="references">References</h2> <ol> <li id="fn:1"><p>mEs – Excited nuclear isomer. <a href="/wiki/Nuclear_isomer" target="_blank">/wiki/Nuclear_isomer</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li> <li id="fn:2"><p>Wang, Meng; Huang, W.J.; Kondev, F.G.; Audi, G.; Naimi, S. (2021). "The AME 2020 atomic mass evaluation (II). Tables, graphs and references*". Chinese Physics C. 45 (3): 030003. doi:10.1088/1674-1137/abddaf. <a href="/wiki/Doi_(identifier)" target="_blank">/wiki/Doi_(identifier)</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li> <li id="fn:3"><p>( ) – Uncertainty (1σ) is given in concise form in parentheses after the corresponding last digits. <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li> <li id="fn:4"><p># – Atomic mass marked #: value and uncertainty derived not from purely experimental data, but at least partly from trends from the Mass Surface (TMS). <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li> <li id="fn:5"><p>Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3): 030001. doi:10.1088/1674-1137/abddae. <a href="https://www-nds.iaea.org/amdc/ame2020/NUBASE2020.pdf" target="_blank">https://www-nds.iaea.org/amdc/ame2020/NUBASE2020.pdf</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></p></li> <li id="fn:6"><p>Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3): 030001. doi:10.1088/1674-1137/abddae. <a href="https://www-nds.iaea.org/amdc/ame2020/NUBASE2020.pdf" target="_blank">https://www-nds.iaea.org/amdc/ame2020/NUBASE2020.pdf</a> <a href="#fnref:6" class="footnote-back-ref">↩</a></p></li> <li id="fn:7"><p>Modes of decay: EC:Electron captureIT:Isomeric transitionSF:Spontaneous fission <a href="/wiki/Electron_capture" target="_blank">/wiki/Electron_capture</a> <a href="#fnref:7" class="footnote-back-ref">↩</a></p></li> <li id="fn:8"><p>Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3): 030001. doi:10.1088/1674-1137/abddae. <a href="https://www-nds.iaea.org/amdc/ame2020/NUBASE2020.pdf" target="_blank">https://www-nds.iaea.org/amdc/ame2020/NUBASE2020.pdf</a> <a href="#fnref:8" class="footnote-back-ref">↩</a></p></li> <li id="fn:9"><p>( ) spin value – Indicates spin with weak assignment arguments. <a href="#fnref:9" class="footnote-back-ref">↩</a></p></li> <li id="fn:10"><p># – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN). <a href="#fnref:10" class="footnote-back-ref">↩</a></p></li> <li id="fn:11"><p># – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN). <a href="#fnref:11" class="footnote-back-ref">↩</a></p></li> <li id="fn:12"><p>Khuyagbaatar, J.; Albers, H. M.; Block, M.; Brand, H.; Cantemir, R. A.; Di Nitto, A.; Düllmann, Ch. E.; Götz, M.; Götz, S.; Heßberger, F. P.; Jäger, E.; Kindler, B.; Kratz, J. V.; Krier, J.; Kurz, N.; Lommel, B.; Lens, L.; Mistry, A.; Schausten, B.; Uusitalo, J.; Yakushev, A. (1 October 2020). "Search for Electron-Capture Delayed Fission in the New Isotope 244Md". Physical Review Letters. 125 (14): 142504. Bibcode:2020PhRvL.125n2504K. doi:10.1103/PhysRevLett.125.142504. PMID 33064498. S2CID 223546973. <a href="http://urn.fi/URN:NBN:fi:jyu-202010066084" target="_blank">http://urn.fi/URN:NBN:fi:jyu-202010066084</a> <a href="#fnref:12" class="footnote-back-ref">↩</a></p></li> <li id="fn:13"><p>Khuyagbaatar, J.; Cantemir, R. A.; Düllmann, Ch. E.; Jäger, E.; Kindler, B.; Krier, J.; Kurz, N.; Lommel, B.; Schausten, B.; Yakushev, A. (2024-03-18). "Decay properties of the neutron-deficient isotope Es 242". Physical Review C. 109 (3). arXiv:2408.01714. doi:10.1103/PhysRevC.109.034311. ISSN 2469-9985. <a href="/wiki/ArXiv_(identifier)" target="_blank">/wiki/ArXiv_(identifier)</a> <a href="#fnref:13" class="footnote-back-ref">↩</a></p></li> <li id="fn:14"><p>Order of ground state and isomer is uncertain. <a href="#fnref:14" class="footnote-back-ref">↩</a></p></li> <li id="fn:15"><p>Order of ground state and isomer is uncertain. <a href="#fnref:15" class="footnote-back-ref">↩</a></p></li> <li id="fn:16"><p>Most common isotope <a href="#fnref:16" class="footnote-back-ref">↩</a></p></li> <li id="fn:17"><p>Theoretically capable of electron capture to 254Cf[1] <a href="#fnref:17" class="footnote-back-ref">↩</a></p></li> <li id="fn:18"><p>Order of ground state and isomer is uncertain. <a href="#fnref:18" class="footnote-back-ref">↩</a></p></li> </ol>