There are 33 known isotopes of molybdenum (Mo) ranging in atomic mass from 83 to 115, as well as four metastable nuclear isomers. Seven isotopes occur naturally, with atomic masses of 92, 94, 95, 96, 97, 98, and 100. Of these naturally occurring isotopes, six (all but 100Mo) have never been observed to decay, but all are theoretically capable of radioactive decay. All unstable isotopes of molybdenum decay into isotopes of zirconium, niobium, technetium, and ruthenium.[1]
Molybdenum-100 is the only naturally occurring isotope which is not stable. Molybdenum-100 has a half-life of approximately 1×1019 y and undergoes double beta decay into ruthenium-100. Molybdenum-98 is the most common isotope, comprising 24.14% of all molybdenum on Earth. Molybdenum isotopes with mass numbers 111 and up all have half-lives of approximately .15 μs.[1]
Standard atomic mass: 95.96(2) u
Contents |
nuclide symbol |
Z(p) | N(n) | isotopic mass (u) |
half-life[n 1] | decay mode(s)[2][n 2] |
daughter isotope(s)[n 3] |
nuclear spin |
representative isotopic composition (mole fraction) |
range of natural variation (mole fraction) |
---|---|---|---|---|---|---|---|---|---|
excitation energy | |||||||||
83Mo | 42 | 41 | 82.94874(54)# | 23(19) ms [6(+30-3) ms] |
β+ | 83Nb | 3/2-# | ||
β+, p | 82Zr | ||||||||
84Mo | 42 | 42 | 83.94009(43)# | 3.8(9) ms [3.7(+10-8) s] |
β+ | 84Nb | 0+ | ||
85Mo | 42 | 43 | 84.93655(30)# | 3.2(2) s | β+ | 85Nb | (1/2-)# | ||
86Mo | 42 | 44 | 85.93070(47) | 19.6(11) s | β+ | 86Nb | 0+ | ||
87Mo | 42 | 45 | 86.92733(24) | 14.05(23) s | β+ (85%) | 87Nb | 7/2+# | ||
β+, p (15%) | 86Zr | ||||||||
88Mo | 42 | 46 | 87.921953(22) | 8.0(2) min | β+ | 88Nb | 0+ | ||
89Mo | 42 | 47 | 88.919480(17) | 2.11(10) min | β+ | 89Nb | (9/2+) | ||
89mMo | 387.5(2) keV | 190(15) ms | IT | 89Mo | (1/2-) | ||||
90Mo | 42 | 48 | 89.913937(7) | 5.56(9) h | β+ | 90Nb | 0+ | ||
90mMo | 2874.73(15) keV | 1.12(5) µs | 8+# | ||||||
91Mo | 42 | 49 | 90.911750(12) | 15.49(1) min | β+ | 91Nb | 9/2+ | ||
91mMo | 653.01(9) keV | 64.6(6) s | IT (50.1%) | 91Mo | 1/2- | ||||
β+ (49.9%) | 91Nb | ||||||||
92Mo | 42 | 50 | 91.906811(4) | Observationally Stable[n 4] | 0+ | 0.1477(31) | |||
92mMo | 2760.46(16) keV | 190(3) ns | 8+ | ||||||
93Mo | 42 | 51 | 92.906813(4) | 4,000(800) a | EC | 93Nb | 5/2+ | ||
93mMo | 2424.89(3) keV | 6.85(7) h | IT (99.88%) | 93Mo | 21/2+ | ||||
β+ (.12%) | 93Nb | ||||||||
94Mo | 42 | 52 | 93.9050883(21) | Observationally Stable[n 5] | 0+ | 0.0923(10) | |||
95Mo[n 6] | 42 | 53 | 94.9058421(21) | Observationally Stable[n 5] | 5/2+ | 0.1590(9) | |||
96Mo | 42 | 54 | 95.9046795(21) | Observationally Stable[n 5] | 0+ | 0.1668(1) | |||
97Mo[n 6] | 42 | 55 | 96.9060215(21) | Observationally Stable[n 5] | 5/2+ | 0.0956(5) | |||
98Mo[n 6] | 42 | 56 | 97.9054082(21) | Observationally Stable[n 7] | 0+ | 0.2419(26) | |||
99Mo[n 6][n 8] | 42 | 57 | 98.9077119(21) | 2.7489(6) d | β- | 99mTc | 1/2+ | ||
99m1Mo | 97.785(3) keV | 15.5(2) µs | 5/2+ | ||||||
99m2Mo | 684.5(4) keV | 0.76(6) µs | 11/2- | ||||||
100Mo[n 9][n 6] | 42 | 58 | 99.907477(6) | 8.5(5)×1018 a | β-β- | 100Ru | 0+ | 0.0967(20) | |
101Mo | 42 | 59 | 100.910347(6) | 14.61(3) min | β- | 101Tc | 1/2+ | ||
102Mo | 42 | 60 | 101.910297(22) | 11.3(2) min | β- | 102Tc | 0+ | ||
103Mo | 42 | 61 | 102.91321(7) | 67.5(15) s | β- | 103Tc | (3/2+) | ||
104Mo | 42 | 62 | 103.91376(6) | 60(2) s | β- | 104Tc | 0+ | ||
105Mo | 42 | 63 | 104.91697(8) | 35.6(16) s | β- | 105Tc | (5/2-) | ||
106Mo | 42 | 64 | 105.918137(19) | 8.73(12) s | β- | 106Tc | 0+ | ||
107Mo | 42 | 65 | 106.92169(17) | 3.5(5) s | β- | 107Tc | (7/2-) | ||
107mMo | 66.3(2) keV | 470(30) ns | (5/2-) | ||||||
108Mo | 42 | 66 | 107.92345(21)# | 1.09(2) s | β- | 108Tc | 0+ | ||
109Mo | 42 | 67 | 108.92781(32)# | 0.53(6) s | β- | 109Tc | (7/2-)# | ||
110Mo | 42 | 68 | 109.92973(43)# | 0.27(1) s | β- (>99.9%) | 110Tc | 0+ | ||
β-, n (<.1%) | 109Tc | ||||||||
111Mo | 42 | 69 | 110.93441(43)# | 200# ms [>300 ns] |
β- | 111Tc | |||
112Mo | 42 | 70 | 111.93684(64)# | 150# ms [>300 ns] |
β- | 112Tc | 0+ | ||
113Mo | 42 | 71 | 112.94188(64)# | 100# ms [>300 ns] |
β- | 113Tc | |||
114Mo | 42 | 72 | 113.94492(75)# | 80# ms [>300 ns] |
0+ | ||||
115Mo | 42 | 73 | 114.95029(86)# | 60# ms [>300 ns] |
Molybdenum-99 is produced commercially by intense neutron-bombardment of a highly purified uranium-235 target, followed rapidly by extraction.[3] It is used as a parent radioisotope in technetium-99m generators to produce the even shorter-lived daughter isotope technetium-99m, which is used in many medical procedures.
Isotopes of niobium | Isotopes of molybdenum | Isotopes of technetium |
Index to isotope pages · Table of nuclides |