Isotopes of mercury

There are seven stable isotopes of mercury (Hg) with 202Hg being the most abundant (29.86%). The longest-lived radioisotopes are 194Hg with a half-life of 444 years, and 203Hg with a half-life of 46.612 days. Most of the remaining radioisotopes have half-lives that are less than a day. 199Hg and 201Hg are the most often studied NMR-active nuclei, having spins of 1/2 and 3/2 respectively.

Mercury-180, producible from thallium-180 was found in 2010 to be capable of an unusual form of spontaneous fission.[1]

Standard atomic mass: 200.59(2) u

Table

nuclide
symbol
Z(p) N(n)  
isotopic mass (u)
 
half-life decay
mode(s)[2][n 1]
daughter
isotope(s)[n 2]
nuclear
spin
representative
isotopic
composition
(mole fraction)
range of natural
variation
(mole fraction)
excitation energy
171Hg 80 91 171.00376(32)# 80(30) µs
[59(+36-16) µs]
3/2-#
172Hg 80 92 171.99883(22) 420(240) µs
[0.25(+35-9) ms]
0
173Hg 80 93 172.99724(22)# 1.1(4) ms
[0.6(+5-2) ms]
3/2-#
174Hg 80 94 173.992864(21) 2.0(4) ms
[2.1(+18-7) ms]
0+
175Hg 80 95 174.99142(11) 10.8(4) ms α 171Pt 5/2-#
176Hg 80 96 175.987355(15) 20.4(15) ms α (98.6%) 172Pt 0+
β+ (1.4%) 176Au
177Hg 80 97 176.98628(8) 127.3(18) ms α (85%) 173Pt 5/2-#
β+ (15%) 177Au
178Hg 80 98 177.982483(14) 0.269(3) s α (70%) 174Pt 0+
β+ (30%) 178Au
179Hg 80 99 178.981834(29) 1.09(4) s α (53%) 175Pt 5/2-#
β+ (47%) 179Au
β+, p (.15%) 178Pt
180Hg[n 3] 80 100 179.978266(15) 2.58(1) s β+ (52%) 180Au 0+
α (48%) 176Pt
SF 100Ru, 80Kr
181Hg 80 101 180.977819(17) 3.6(1) s β+ (64%) 181Au 1/2(-)
α (36%) 177Pt
β+, p (.014%) 180Pt
β+, α (9×10−6%) 177Ir
181mHg 210(40)# keV 13/2+
182Hg 80 102 181.97469(1) 10.83(6) s β+ (84.8%) 182Au 0+
α (15.2%) 178Pt
β+, p (10−5%) 181Pt
183Hg 80 103 182.974450(9) 9.4(7) s β+ (74.5%) 183Au 1/2-
α (25.5%) 179Pt
β+, p (5.6×10−4%) 182Pt
183m1Hg 198(14) keV 13/2+#
183m2Hg 240(40)# keV 5# s β+ 183Au 13/2+#
184Hg 80 104 183.971713(11) 30.6(3) s β+ (98.89%) 184Au 0+
α (1.11%) 180Pt
185Hg 80 105 184.971899(17) 49.1(10) s β+ (94%) 185Au 1/2-
α (6%) 181Pt
185mHg 99.3(5) keV 21.6(15) s IT (54%) 185Hg 13/2+
β+ (46%) 185Au
α (.03%) 181Pt
186Hg 80 106 185.969362(12) 1.38(6) min β+ (99.92%) 186Au 0+
α (.016%) 182Pt
186mHg 2217.3(4) keV 82(5) µs (8-)
187Hg 80 107 186.969814(15) 1.9(3) min β+ 187Au 3/2-
α (1.2×10−4%) 183Pt
187mHg 59(16) keV 2.4(3) min β+ 187Au 13/2+
α (2.5×10−4%) 183Pt
188Hg 80 108 187.967577(12) 3.25(15) min β+ 188Au 0+
α (3.7×10−5%) 184Pt
188mHg 2724.3(4) keV 134(15) ns (12+)
189Hg 80 109 188.96819(4) 7.6(1) min β+ 189Au 3/2-
α (3×10−5%) 185Pt
189mHg 80(30) keV 8.6(1) min β+ 189Au 13/2+
α (3×10−5%) 185Pt
190Hg 80 110 189.966322(17) 20.0(5) min β+ 190Au 0+
α (5×10−5%) 186Pt
191Hg 80 111 190.967157(24) 49(10) min β+ 191Au 3/2(-)
191mHg 128(22) keV 50.8(15) min β+ 191Au 13/2+
192Hg 80 112 191.965634(17) 4.85(20) h EC 192Au 0+
α (4×10−6%) 188Pt
193Hg 80 113 192.966665(17) 3.80(15) h β+ 193Au 3/2-
193mHg 140.76(5) keV 11.8(2) h β+ (92.9%) 193Au 13/2+
IT (7.1%) 193Hg
194Hg 80 114 193.965439(13) 444(77) a EC 194Au 0+
195Hg 80 115 194.966720(25) 10.53(3) h β+ 195Au 1/2-
195mHg 176.07(4) keV 41.6(8) h IT (54.2%) 195Hg 13/2+
β+ (45.8%) 195Au
196Hg 80 116 195.965833(3) Observationally Stable[n 4] 0+ 0.0015(1)
197Hg 80 117 196.967213(3) 64.14(5) h EC 197Au 1/2-
197mHg 298.93(8) keV 23.8(1) h IT (91.4%) 197Hg 13/2+
EC (8.6%) 197Au
198Hg 80 118 197.9667690(4) Observationally Stable[n 5] 0+ 0.0997(20)
199Hg 80 119 198.9682799(4) Observationally Stable[n 6] 1/2- 0.1687(22)
199mHg 532.48(10) keV 42.66(8) min IT 199Hg 13/2+
200Hg 80 120 199.9683260(4) Observationally Stable[n 7] 0+ 0.2310(19)
201Hg 80 121 200.9703023(6) Observationally Stable[n 8] 3/2- 0.1318(9)
201mHg 766.22(15) keV 94(3) µs 13/2+
202Hg 80 122 201.9706430(6) Observationally Stable[n 9] 0+ 0.2986(26)
203Hg 80 123 202.9728725(18) 46.595(6) d β- 203Tl 5/2-
203mHg 933.14(23) keV 24(4) µs (13/2+)
204Hg 80 124 203.9734939(4) Observationally Stable[n 10] 0+ 0.0687(15)
205Hg 80 125 204.976073(4) 5.14(9) min β- 205Tl 1/2-
205mHg 1556.40(17) keV 1.09(4) ms IT 205Hg 13/2+
206Hg 80 126 205.977514(22) 8.15(10) min β- 206Tl 0+
207Hg 80 127 206.98259(16) 2.9(2) min β- 207Tl (9/2+)
208Hg 80 128 207.98594(32)# 42(5) min
[41(+5-4) min]
β- 208Tl 0+
209Hg 80 129 208.99104(21)# 37(8) s 9/2+#
210Hg 80 130 209.99451(32)# 10# min
[>300 ns]
0+
  1. ^ Abbreviations:
    EC: Electron capture
    IT: Isomeric transition
  2. ^ Bold for stable isotopes
  3. ^ When produced from 180Tl can also undergo fission to 100Ru and 80Kr
  4. ^ Believed to undergo α decay to 192Pt or β+β+ decay to 196Pt with a half-life over 2.5×1018 years
  5. ^ Believed to undergo α decay to 194Pt
  6. ^ Believed to undergo α decay to 195Pt
  7. ^ Believed to undergo α decay to 196Pt
  8. ^ Believed to undergo α decay to 197Pt
  9. ^ Believed to undergo α decay to 198Pt
  10. ^ Believed to undergo α decay to 200Pt or β-β- decay to 204Pb

Notes

References

Isotopes of gold Isotopes of mercury Isotopes of thallium
Index to isotope pages · Table of nuclides