Isotopes of molybdenum

Isotopes of molybdenum (₄₂Mo)
γ	–
Standard atomic weight Ar°(Mo)
	95.95±0.01; 95.95±0.01 (abridged);
	view; talk; edit;

There are 33 known isotopes of molybdenum (₄₂Mo) 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.^[5]

Molybdenum-100 is the only naturally occurring isotope that 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.^[5]

List of isotopes

nuclide symbol	Z(p)	N(n)	isotopic mass (u)	half-life^{[n 1]}	decay mode(s)^[6]^{[n 2]}	daughter isotope(s)^{[n 3]}	nuclear spin	representative isotopic composition (mole fraction)	range of natural variation (mole fraction)
nuclide symbol	excitation energy			half-life^{[n 1]}	decay mode(s)^[6]^{[n 2]}	daughter isotope(s)^{[n 3]}	nuclear spin	representative isotopic composition (mole fraction)	range of natural variation (mole fraction)
⁸³Mo	42	41	82.94874(54)#	23(19) ms [6(+30-3) ms]	β⁺	⁸³Nb	3/2−#
⁸³Mo	42	41	82.94874(54)#	23(19) ms [6(+30-3) ms]	β⁺, p	⁸²Zr	3/2−#
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+#
⁸⁷Mo	42	45	86.92733(24)	14.05(23) s	β⁺, p (15%)	⁸⁶Zr	7/2+#
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−
^91mMo	653.01(9) keV			64.6(6) s	β⁺ (49.9%)	⁹¹Nb	1/2−
⁹²Mo	42	50	91.906811(4)	Observationally Stable^{[n 4]}			0+	0.14649(106)
^92mMo	2760.46(16) keV			190(3) ns			8+
⁹³Mo	42	51	92.906813(4)	4,000(800) y	EC	⁹³Nb	5/2+
^93mMo	2424.89(3) keV			6.85(7) h	IT (99.88%)	⁹³Mo	21/2+
^93mMo	2424.89(3) keV			6.85(7) h	β⁺ (.12%)	⁹³Nb	21/2+
⁹⁴Mo	42	52	93.9050883(21)	Stable^{[n 5]}			0+	0.09187(33)
⁹⁵Mo^{[n 6]}	42	53	94.9058421(21)	Stable^{[n 5]}			5/2+	0.15873(30)
⁹⁶Mo	42	54	95.9046795(21)	Stable^{[n 5]}			0+	0.16673(30)
⁹⁷Mo^{[n 6]}	42	55	96.9060215(21)	Stable^{[n 5]}			5/2+	0.09582(15)
⁹⁸Mo^{[n 6]}	42	56	97.90540482(21)	Observationally Stable^{[n 7]}			0+	0.24292(80)
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+	0.09744(65)
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+
¹¹⁰Mo	42	68	109.92973(43)#	0.27(1) s	β⁻, n (<.1%)	¹⁰⁹Tc	0+
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]

^ Bold for isotopes with half-lives longer than the age of the universe (nearly stable)
^ Abbreviations:
EC: Electron capture
IT: Isomeric transition
^ Bold for stable isotopes
^ Believed to decay by β⁺β⁺ to ⁹²Zr with a half-life over 1.9×10²⁰ years
^ ^a ^b ^c ^d Believed to be capable of spontaneous fission
^ ^a ^b ^c ^d ^e Fission product
^ Believed to decay by β⁻β⁻ to ⁹⁸Ru with a half-life of over 1×10¹⁴ years
^ Used to produce the medically useful radioisotope technetium-99m
^ Primordial radionuclide

Notes

Geologically exceptional samples are known in which the isotopic composition lies outside the reported range. The uncertainty in the atomic mass may exceed the stated value for such specimens.
Values marked # are not purely derived from experimental data, but at least partly from systematic trends. Spins with weak assignment arguments are enclosed in parentheses.
Uncertainties are given in concise form in parentheses after the corresponding last digits. Uncertainty values denote one standard deviation, except isotopic composition and standard atomic mass from IUPAC, which use expanded uncertainties.

Applications

Molybdenum-99 is produced commercially by intense neutron-bombardment of a highly purified uranium-235 target, followed rapidly by extraction.^[7] 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.

References

^ ^a ^b 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.
^ Kajan, I.; Heinitz, S.; Kossert, K.; Sprung, P.; Dressler, R.; Schumann, D. (2021-10-05). "First direct determination of the ⁹³Mo half-life". Scientific Reports. 11 (1). doi:10.1038/s41598-021-99253-5. ISSN 2045-2322. PMC 8492754. PMID 34611245.
^ "Standard Atomic Weights: Molybdenum". CIAAW. 2013.
^ Prohaska, Thomas; Irrgeher, Johanna; Benefield, Jacqueline; Böhlke, John K.; Chesson, Lesley A.; Coplen, Tyler B.; Ding, Tiping; Dunn, Philip J. H.; Gröning, Manfred; Holden, Norman E.; Meijer, Harro A. J. (2022-05-04). "Standard atomic weights of the elements 2021 (IUPAC Technical Report)". Pure and Applied Chemistry. doi:10.1515/pac-2019-0603. ISSN 1365-3075.
^ ^a ^b D. R. Lide, ed. (2006). CRC Handbook of Chemistry and Physics. Vol. 11. CRC Press. pp. 87–88. ISBN 0-8493-0487-3.
^ "Universal Nuclide Chart". nucleonica. {{cite web}}: Unknown parameter |registration= ignored (|url-access= suggested) (help)
^ Frank N. Von Hippel; Laura H. Kahn (December 2006). "Feasibility of Eliminating the Use of Highly Enriched Uranium in the Production of Medical Radioisotopes". Science & Global Security. 14 (2 & 3): 151–162. doi:10.1080/08929880600993071. Retrieved 2010-03-26.

Isotope masses from:
- G. Audi; A. H. Wapstra; C. Thibault; J. Blachot; O. Bersillon (2003). "The NUBASE evaluation of nuclear and decay properties" (PDF). Nuclear Physics A. 729: 3–128. Bibcode:2003NuPhA.729....3A. doi:10.1016/j.nuclphysa.2003.11.001. Archived from the original (PDF) on 2008-09-23. {{cite journal}}: Unknown parameter |deadurl= ignored (|url-status= suggested) (help)
Isotopic compositions and standard atomic masses from:
- J. R. de Laeter; J. K. Böhlke; P. De Bièvre; H. Hidaka; H. S. Peiser; K. J. R. Rosman; P. D. P. Taylor (2003). "Atomic weights of the elements. Review 2000 (IUPAC Technical Report)". Pure and Applied Chemistry. 75 (6): 683–800. doi:10.1351/pac200375060683.
- M. E. Wieser; M. Berglund (2009). "Atomic weights of the elements 2007 (IUPAC Technical Report)" (PDF). Pure and Applied Chemistry. 81 (11): 2131–2156. doi:10.1351/PAC-REP-09-08-03. {{cite journal}}: Unknown parameter |laysummary= ignored (help)
Half-life, spin, and isomer data selected from the following sources. See editing notes on this article's talk page.
- G. Audi; A. H. Wapstra; C. Thibault; J. Blachot; O. Bersillon (2003). "The NUBASE evaluation of nuclear and decay properties" (PDF). Nuclear Physics A. 729: 3–128. Bibcode:2003NuPhA.729....3A. doi:10.1016/j.nuclphysa.2003.11.001. Archived from the original (PDF) on 2008-09-23. {{cite journal}}: Unknown parameter |deadurl= ignored (|url-status= suggested) (help)
- National Nuclear Data Center. "NuDat 2.1 database". Brookhaven National Laboratory. Retrieved 23 February 2017.
- N. E. Holden (2004). "Table of the Isotopes". In D. R. Lide (ed.). CRC Handbook of Chemistry and Physics (85th ed.). CRC Press. Section 11. ISBN 978-0-8493-0485-9. {{cite book}}: Unknown parameter |nopp= ignored (|no-pp= suggested) (help)

[6] Bold for isotopes with half-lives longer than the age of the universe (nearly stable)

[8] Abbreviations:
EC: Electron capture
IT: Isomeric transition

[9] Bold for stable isotopes

[10] Believed to decay by β⁺β⁺ to ⁹²Zr with a half-life over 1.9×10²⁰ years

[SF-11] Believed to be capable of spontaneous fission

[FP-12] Fission product

[13] Believed to decay by β⁻β⁻ to ⁹⁸Ru with a half-life of over 1×10¹⁴ years

[14] Used to produce the medically useful radioisotope technetium-99m

[15] Primordial radionuclide

[NUBASE2020-1] 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.

[93Mo-2] Kajan, I.; Heinitz, S.; Kossert, K.; Sprung, P.; Dressler, R.; Schumann, D. (2021-10-05). "First direct determination of the ⁹³Mo half-life". Scientific Reports. 11 (1). doi:10.1038/s41598-021-99253-5. ISSN 2045-2322. PMC 8492754. PMID 34611245.

[3] "Standard Atomic Weights: Molybdenum". CIAAW. 2013.

[CIAAW2021-4] Prohaska, Thomas; Irrgeher, Johanna; Benefield, Jacqueline; Böhlke, John K.; Chesson, Lesley A.; Coplen, Tyler B.; Ding, Tiping; Dunn, Philip J. H.; Gröning, Manfred; Holden, Norman E.; Meijer, Harro A. J. (2022-05-04). "Standard atomic weights of the elements 2021 (IUPAC Technical Report)". Pure and Applied Chemistry. doi:10.1515/pac-2019-0603. ISSN 1365-3075.

[CRCisotopes-5] D. R. Lide, ed. (2006). CRC Handbook of Chemistry and Physics. Vol. 11. CRC Press. pp. 87–88. ISBN 0-8493-0487-3.

[7] "Universal Nuclide Chart". nucleonica. {{cite web}}: Unknown parameter |registration= ignored (|url-access= suggested) (help)

[16] Frank N. Von Hippel; Laura H. Kahn (December 2006). "Feasibility of Eliminating the Use of Highly Enriched Uranium in the Production of Medical Radioisotopes". Science & Global Security. 14 (2 & 3): 151–162. doi:10.1080/08929880600993071. Retrieved 2010-03-26.

[1]

[2]

[3]

[4]

[5]

[n 1]

[6]

[n 2]

[n 3]

[n 4]

[n 5]

[n 6]

[n 7]

[n 8]

[n 9]

[7]