View source for Isotopes of technetium

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{{Infobox technetium isotopes}}
[[Technetium]] (<sub>43</sub>Tc) is one of the two elements with {{nowrap|''Z'' < 83}} that have no stable [[isotope]]s; the other such element is [[promethium]].<ref name="IUPAC 2011">{{cite web |url=http://publications.iupac.org/pac/pdf/2013/pdf/8505x1047.pdf |title=Atomic weights of the elements 2011 (IUPAC Technical Report) |publisher=[[IUPAC]] |access-date=August 11, 2014 |page=1059(13)}}&nbsp;– Elements marked with a * have no stable isotope: 43, 61, and 83 and up.</ref> It is primarily artificial, with only trace quantities existing in nature produced by [[spontaneous fission]] (there are an estimated {{val|2.5|e=−13}} grams of <sup>99</sup>Tc per gram of [[pitchblende]])<ref name="TcGeochem">{{cite report |last1=Icenhower |first1=J.P. |last2=Martin |first2=W.J. |last3=Qafoku |first3=N.P. |last4=Zachara |first4=J.M. |date=2008 |title=The Geochemistry of Technetium: A Summary of the Behavior of an Artificial Element in the Natural Environment |publisher=U.S. Department of Energy |location=Pacific Northwest National Laboratory |page=2.1}}</ref> or [[neutron capture]] by [[molybdenum]]. The element was first obtained in 1936 from bombarded [[molybdenum]], the first artificial element to be produced. The most stable [[radionuclide|radioisotope]]s are <sup>97</sup>Tc ([[half-life]] of 4.21 million years), <sup>98</sup>Tc (half-life: 4.2 million years), and <sup>99</sup>Tc (half-life: 211,100 years).

Thirty-three other radioisotopes have been characterized with [[atomic mass]]es ranging from <sup>85</sup>Tc to <sup>120</sup>Tc.<ref>{{NNDC}}</ref> Those with half-lives more than an hour have masses 93 to 96.

Technetium also has numerous [[nuclear isomer|meta states]]. <sup>97m</sup>Tc is the most stable, with a half-life of 91.0 days (0.097&nbsp;MeV), followed by <sup>95m</sup>Tc (half-life: 61 days, 0.038&nbsp;MeV) and [[technetium-99m|<sup>99m</sup>Tc]] (half-life: 6.04 hours, 0.143&nbsp;MeV). <sup>99m</sup>Tc emits only [[gamma ray]]s while decaying to <sup>99</sup>Tc.

For isotopes lighter than <sup>98</sup>Tc, the primary [[decay mode]] is [[electron capture]] to [[isotopes of molybdenum]]. For the heavier isotopes, the primary mode is [[beta decay|beta emission]] to [[isotopes of ruthenium]], with the exception that <sup>100</sup>Tc can decay both by beta emission and electron capture.

[[Technetium-99m]] is the technetium isotope employed in the [[nuclear medicine]] industry. Its low-energy [[isomeric transition]], which yields a gamma-ray at ~140.5&nbsp;keV, is ideal for imaging using [[Single-photon emission computed tomography|Single Photon Emission Computed Tomography (SPECT)]].  Several technetium isotopes, such as <sup>94m</sup>Tc, <sup>95</sup>Tc, and <sup>96</sup>Tc, which are produced via (p,n) reactions using a [[cyclotron]] on [[molybdenum]] targets, have also been identified as potential [[Positron emission tomography|Positron Emission Tomography (PET)]] or gamma-emitting agents for medical imaging.<ref>{{Cite journal|last1=Bigott|first1=H. M.|last2=Mccarthy|first2=D. W.|last3=Wüst|first3=F. R.|last4=Dahlheimer|first4=J. L.|last5=Piwnica-Worms|first5=D. R.|last6=Welch|first6=M. J.|date=2001|title=Production, processing and uses of 94mTc|url=|journal=Journal of Labelled Compounds and Radiopharmaceuticals|language=en|volume=44|issue=S1|pages=S119–S121|doi=10.1002/jlcr.2580440141|issn=1099-1344}}</ref><ref>{{Cite journal|last1=Morley|first1=Thomas|last2=Benard|first2=Francois|last3=Schaffer|first3=Paul|last4=Buckley|first4=Kenneth|last5=Hoehr|first5=Cornelia|last6=Gagnon|first6=Katherine|last7=McQuarrie|first7=Steve|last8=Kovacs|first8=Michael|last9=Ruth|first9=Thomas|date=2011-05-01|title=Simple, rapid production of Tc-94m|url=https://jnm.snmjournals.org/content/52/supplement_1/290|journal=Journal of Nuclear Medicine|language=en|volume=52|issue=supplement 1|pages=290|issn=0161-5505}}</ref><ref>{{Cite journal|last1=Hayakawa|first1=Takehito|last2=Hatsukawa|first2=Yuichi|last3=Tanimori|first3=Toru|date=January 2018|title=95g Tc and 96g Tc as alternatives to medical radioisotope 99m Tc|url=|journal=Heliyon|volume=4|issue=1|pages=e00497|doi=10.1016/j.heliyon.2017.e00497|doi-access=free |issn=2405-8440|pmc=5766687|pmid=29349358|bibcode=2018Heliy...400497H }}</ref> Technetium-101 has been produced using a [[D-D fusion]]-based [[neutron generator]] from the <sup>100</sup>Mo(n,γ)<sup>101</sup>Mo reaction on natural molybdenum and subsequent [[Beta decay|beta-minus decay]] of <sup>101</sup>Mo to <sup>101</sup>Tc. Despite its shorter half-life (i.e., 14.22 min), <sup>101</sup>Tc exhibits unique decay characteristics suitable for radioisotope diagnostic or [[Radiation therapy|therapeutic]] procedures, where it has been proposed that its implementation, as a supplement for dual-isotopic imaging or replacement for <sup>99m</sup>Tc, could be performed by on-site production and dispensing at the point of patient care.<ref>{{Cite journal|last1=Mausolf|first1=Edward J.|last2=Johnstone|first2=Erik V.|last3=Mayordomo|first3=Natalia|last4=Williams|first4=David L.|last5=Guan|first5=Eugene Yao Z.|last6=Gary|first6=Charles K.|date=September 2021|title=Fusion-Based Neutron Generator Production of Tc-99m and Tc-101: A Prospective Avenue to Technetium Theranostics|journal=Pharmaceuticals|language=en|volume=14|issue=9|pages=875|doi=10.3390/ph14090875|pmc=8467155|pmid=34577575|doi-access=free}}</ref>

[[Technetium-99]] is the most common and most readily available isotope, as it is a major [[fission product]] from fission of [[actinide]]s like [[uranium]] and [[plutonium]] with a [[fission product yield]] of 6% or more, and in fact the most significant [[long-lived fission product]]. Lighter isotopes of technetium are almost never produced in fission because the initial fission products normally have a higher neutron/proton ratio than is stable for their mass range, and therefore undergo [[beta decay]] until reaching the ultimate product. Beta decay of fission products of mass 98 and lower, or 100, stops at stable (or very long-lived) isotopes of lower atomic number and does not reach technetium. For greater masses, the technetium isotopes are very short-lived and quickly undergo further beta decay. Therefore, the technetium in [[spent nuclear fuel]] is practically all <sup>99</sup>Tc. In the presence of [[fast neutron]]s a small amount of {{chem|98|Tc}} will be produced by (n,2n) "knockout" reactions. If [[nuclear transmutation]] of fission-derived technetium, or technetium wastes from medical applications, is desired, fast neutrons are therefore not desirable as the long lived {{chem|98|Tc}} increases rather than reducing the longevity of the radioactivity in the material. {{citation needed|date=June 2025}}

One gram of <sup>99</sup>Tc produces {{val|6.2|e=8}} disintegrations a second (that is, 0.62&nbsp;G[[Becquerel|Bq]]/g).<ref>''The Encyclopedia of the Chemical Elements'', p. 693, "Toxicology", paragraph 2</ref>

Technetium has no [[primordial isotope]]s and does not occur in nature in significant quantities, and thus a [[standard atomic weight]] cannot be given.

==List of isotopes==
{{Anchor|Technetium-83|Technetium-84|Technetium-85|Technetium-87m1|Technetium-87m2}}

<!--Please delete anchor(s) from the list above or table below if adding a dedicated isotope section(s).-->

{{Isotopes table
|symbol=Tc
|refs=NUBASE2020, AME2020 II<!-- updated 2024-10-19 -->
|notes=m, unc(), mass#, exen#, spin(), spin#, daughter-st, daughter-nst, n, p, IT, EC
}}
|-id=Technetium-86
| <sup>86</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 43
| 85.94464(32)#
| 55(7)&nbsp;ms
| [[beta decay|β<sup>+</sup>]]
| <sup>86</sup>Mo
| (0+)
|
|-id=Technetium-86m
| style="text-indent:1em" | <sup>86m</sup>Tc
| colspan="3" style="text-indent:2em" | 1524(10)&nbsp;keV
| 1.10(12)&nbsp;μs
| [[isomeric transition|IT]]
| <sup>86</sup>Tc
| (6+)
|
|-id=Technetium-87
| rowspan=2|<sup>87</sup>Tc
| rowspan=2 style="text-align:right" | 43
| rowspan=2 style="text-align:right" | 44
| rowspan=2|86.9380672(45)
| rowspan=2|2.14(17)&nbsp;s
| β<sup>+</sup>
| <sup>87</sup>Mo
| rowspan=2|9/2+#
| rowspan=2|
|-
| β<sup>+</sup>, [[proton emission|p]] (<0.7%)
| <sup>86</sup>Nb
|-id=Technetium-87m
| style="text-indent:1em" | <sup>87m</sup>Tc
| colspan="3" style="text-indent:2em" | 71(1)&nbsp;keV
| 647(24)&nbsp;ns
| IT
| <sup>87</sup>Tc
| 7/2+#
|
|-id=Technetium-88
| <sup>88</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 45
| 87.9337942(44)
| 6.4(8)&nbsp;s
| β<sup>+</sup>
| <sup>88</sup>Mo
| (2+)
|
|-id=Technetium-88m1
| style="text-indent:1em" | <sup>88m1</sup>Tc
| colspan="3" style="text-indent:2em" | 70(3)&nbsp;keV
| 5.8(2)&nbsp;s
| β<sup>+</sup>
| <sup>88</sup>Mo
| (6+)
|
|-id=Technetium-88m2
| style="text-indent:1em" | <sup>88m2</sup>Tc
| colspan="3" style="text-indent:2em" | 95(1)&nbsp;keV
| 146(12)&nbsp;ns
| IT
| <sup>88</sup>Tc
| (4+)
|
|-id=Technetium-89
| <sup>89</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 46
| 88.9276486(41)
| 12.8(9)&nbsp;s
| β<sup>+</sup>
| <sup>89</sup>Mo
| (9/2+)
|
|-id=Technetium-89m
| style="text-indent:1em" | <sup>89m</sup>Tc
| colspan="3" style="text-indent:2em" | 62.6(5)&nbsp;keV
| 12.9(8)&nbsp;s
| β<sup>+</sup>
| <sup>89</sup>Mo
| (1/2−)
|
|-id=Technetium-90
| <sup>90</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 47
| 89.9240739(11)
| 49.2(4)&nbsp;s
| β<sup>+</sup>
| <sup>90</sup>Mo
| (8+)
|
|-id=Technetium-90m
| style="text-indent:1em" | <sup>90m</sup>Tc
| colspan="3" style="text-indent:2em" | 144.0(17)&nbsp;keV
| 8.7(2)&nbsp;s
| β<sup>+</sup>
| <sup>90</sup>Mo
| 1+
|
|-id=Technetium-91
| <sup>91</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 48
| 90.9184250(25)
| 3.14(2)&nbsp;min
| β<sup>+</sup>
| <sup>91</sup>Mo
| (9/2)+
|
|-id=Technetium-91m
| style="text-indent:1em" | <sup>91m</sup>Tc
| colspan="3" style="text-indent:2em" | 139.3(3)&nbsp;keV
| 3.3(1)&nbsp;min
| β<sup>+</sup> (99%)
| <sup>91</sup>Mo
| (1/2)−
| 
|-id=Technetium-92
| <sup>92</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 49
| 91.9152698(33)
| 4.25(15)&nbsp;min
| β<sup>+</sup>
| '''<sup>92</sup>Mo'''
| (8)+
|
|-id=Technetium-92m1
| style="text-indent:1em" | <sup>92m1</sup>Tc
| colspan="3" style="text-indent:2em" | 270.09(8)&nbsp;keV
| 1.03(6)&nbsp;μs
| IT
| <sup>92</sup>Tc
| (4+)
|
|-id=Technetium-92m2
| style="text-indent:1em" | <sup>92m2</sup>Tc
| colspan="3" style="text-indent:2em" | 529.42(13)&nbsp;keV
| <0.1&nbsp;μs
| IT
| <sup>92</sup>Tc
| (3+)
|
|-id=Technetium-92m3
| style="text-indent:1em" | <sup>92m3</sup>Tc
| colspan="3" style="text-indent:2em" | 711.33(15)&nbsp;keV
| <0.1&nbsp;μs
| IT
| <sup>92</sup>Tc
| 1+
|
|-id=Technetium-93
| <sup>93</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 50
| 92.9102451(11)
| 2.75(5)&nbsp;h
| β<sup>+</sup>
| <sup>93</sup>Mo
| 9/2+
|
|-id=Technetium-93m1
| rowspan=2 style="text-indent:1em" | <sup>93m1</sup>Tc
| rowspan=2 colspan="3" style="text-indent:2em" | 391.84(8)&nbsp;keV
| rowspan=2|43.5(10)&nbsp;min
| IT (77.4%)
| <sup>93</sup>Tc
| rowspan=2|1/2−
| rowspan=2|
|-
| β<sup>+</sup> (22.6%)
| <sup>93</sup>Mo
|-id=Technetium-93m2
| style="text-indent:1em" | <sup>93m2</sup>Tc
| colspan="3" style="text-indent:2em" | 2185.16(15)&nbsp;keV
| 10.2(3)&nbsp;μs
| IT
| <sup>93</sup>Tc
| (17/2)−
|
|-id=Technetium-94
| <sup>94</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 51
| 93.9096523(44)
| 293(1)&nbsp;min
| β<sup>+</sup>
| '''<sup>94</sup>Mo'''
| 7+
|
|-id=Technetium-94m
| rowspan=2 style="text-indent:1em" | <sup>94m</sup>Tc
| rowspan=2 colspan="3" style="text-indent:2em" | 76(3)&nbsp;keV
| rowspan=2|52(1)&nbsp;min
| β<sup>+</sup> (>99.82%)
| '''<sup>94</sup>Mo'''
| rowspan=2|(2)+
| rowspan=2|
|-
| IT (<0.18%)
| <sup>94</sup>Tc
|-id=Technetium-95
| <sup>95</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 52
| 94.9076523(55)
| 19.258(26)&nbsp;h
| β<sup>+</sup>
| '''<sup>95</sup>Mo'''
| 9/2+
|
|-id=Technetium-95m
| rowspan=2 style="text-indent:1em" | <sup>95m</sup>Tc
| rowspan=2 colspan="3" style="text-indent:2em" | 38.91(4)&nbsp;keV
| rowspan=2|61.96(24)&nbsp;d
| β<sup>+</sup> (96.1%)
| '''<sup>95</sup>Mo'''
| rowspan=2|1/2−
| rowspan=2|
|-
| IT (3.9%)
| <sup>95</sup>Tc
|-id=Technetium-96
| <sup>96</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 53
| 95.9078667(55)
| 4.28(7)&nbsp;d
| β<sup>+</sup>
| '''<sup>96</sup>Mo'''
| 7+
|
|-id=Technetium-96m
| rowspan=2 style="text-indent:1em" | <sup>96m</sup>Tc
| rowspan=2 colspan="3" style="text-indent:2em" | 34.23(4)&nbsp;keV
| rowspan=2|51.5(10)&nbsp;min
| IT (98.0%)
| <sup>96</sup>Tc
| rowspan=2|4+
| rowspan=2|
|-
| β<sup>+</sup> (2.0%)
| '''<sup>96</sup>Mo'''
|-id=Technetium-97
| <sup>97</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 54
| 96.9063607(44)
| 4.21(16)×10<sup>6</sup>&nbsp;y
| [[Electron capture|EC]]
| '''<sup>97</sup>Mo'''
| 9/2+
|
|-id=Technetium-97m
| rowspan=2 style="text-indent:1em" | <sup>97m</sup>Tc
| rowspan=2 colspan="3" style="text-indent:2em" | 96.57(6)&nbsp;keV
| rowspan=2|91.1(6)&nbsp;d
| IT (96.06%)
| <sup>97</sup>Tc
| rowspan=2|1/2−
| rowspan=2|
|-
| EC (3.94%)
| '''<sup>97</sup>Mo'''
|-id=Technetium-98
| <sup>98</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 55
| 97.9072112(36)
| 4.2(3)×10<sup>6</sup> y
| β<sup>−</sup>
| '''<sup>98</sup>Ru'''
| 6+
|
|-id=Technetium-98m
| style="text-indent:1em" | <sup>98m</sup>Tc
| colspan="3" style="text-indent:2em" | 90.77(16)&nbsp;keV
| 14.7(5)&nbsp;μs
| IT
| <sup>98</sup>Tc
| (2,3)−
|
|-
| [[Technetium-99|<sup>99</sup>Tc]]<ref group="n">[[Long-lived fission product]]</ref>
| style="text-align:right" | 43
| style="text-align:right" | 56
| 98.90624968(97)
| 2.111(12)×10<sup>5</sup>&nbsp;y
| β<sup>−</sup>
| '''<sup>99</sup>Ru'''
| 9/2+
| trace
|-
| rowspan=2 style="text-indent:1em" | [[Technetium-99m|<sup>99m</sup>Tc]]<ref group="n">[[Fission product]]</ref><ref group="n">Used in medicine</ref>
| rowspan=2 colspan="3" style="text-indent:2em" | 142.6836(11)&nbsp;keV
| rowspan=2|6.0066(2)&nbsp;h
| IT
| <sup>99</sup>Tc
| rowspan=2|1/2−
| rowspan=2|
|-
| β<sup>−</sup> (0.0037%)
| '''<sup>99</sup>Ru'''
|-id=Technetium-100
| rowspan=2|<sup>100</sup>Tc
| rowspan=2 style="text-align:right" | 43
| rowspan=2 style="text-align:right" | 57
| rowspan=2|99.9076527(15)
| rowspan=2|15.46(19)&nbsp;s
| β<sup>−</sup>
| '''<sup>100</sup>Ru'''
| rowspan=2|1+
| rowspan=2|
|-
| EC (0.0018%)
| '''''<sup>100</sup>Mo'''''
|-id=Technetium-100m1
| style="text-indent:1em" | <sup>100m1</sup>Tc
| colspan="3" style="text-indent:2em" | 200.67(4)&nbsp;keV
| 8.32(14)&nbsp;μs
| IT
| <sup>100</sup>Tc
| (4)+
|
|-id=Technetium-100m2
| style="text-indent:1em" | <sup>100m2</sup>Tc
| colspan="3" style="text-indent:2em" | 243.95(4)&nbsp;keV
| 3.2(2)&nbsp;μs
| IT
| <sup>100</sup>Tc
| (6)+
|
|-id=Technetium-101
| <sup>101</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 58
| 100.907305(26)
| 14.22(1)&nbsp;min
| β<sup>−</sup>
| '''<sup>101</sup>Ru'''
| 9/2+
|
|-id=Technetium-101m
| style="text-indent:1em" | <sup>101m</sup>Tc
| colspan="3" style="text-indent:2em" | 207.526(20)&nbsp;keV
| 636(8)&nbsp;μs
| IT
| <sup>101</sup>Tc
| 1/2−
|
|-id=Technetium-102
| <sup>102</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 59
| 101.9092072(98)
| 5.28(15)&nbsp;s
| β<sup>−</sup>
| '''<sup>102</sup>Ru'''
| 1+
|
|-id=Technetium-102m
| style="text-indent:1em" | <sup>102m</sup>Tc<ref group="n" name="order">Order of ground state and isomer is uncertain.</ref>
| colspan="3" style="text-indent:2em" | 50(50)#&nbsp;keV
| 4.35(7)&nbsp;min
| β<sup>−</sup>
| '''<sup>102</sup>Ru'''
| (4+)
| 
|-id=Technetium-103
| <sup>103</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 60
| 102.909174(11)
| 54.2(8)&nbsp;s
| β<sup>−</sup>
| <sup>103</sup>Ru
| 5/2+
|
|-id=Technetium-104
| <sup>104</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 61
| 103.911434(27)
| 18.3(3)&nbsp;min
| β<sup>−</sup>
| '''<sup>104</sup>Ru'''
| (3−)
|
|-id=Technetium-104m1
| style="text-indent:1em" | <sup>104m1</sup>Tc
| colspan="3" style="text-indent:2em" | 69.7(2)&nbsp;keV
| 3.5(3)&nbsp;μs
| IT
| <sup>104</sup>Tc
| (5−)
|
|-id=Technetium-104m2
| style="text-indent:1em" | <sup>104m2</sup>Tc
| colspan="3" style="text-indent:2em" | 106.1(3)&nbsp;keV
| 400(20)&nbsp;ns
| IT
| <sup>104</sup>Tc
| 4#
|
|-id=Technetium-105
| <sup>105</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 62
| 104.911662(38)
| 7.64(6)&nbsp;min
| β<sup>−</sup>
| <sup>105</sup>Ru
| (3/2−)
|
|-id=Technetium-106
| <sup>106</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 63
| 105.914357(13)
| 35.6(6)&nbsp;s
| β<sup>−</sup>
| <sup>106</sup>Ru
| (1,2)(+#)
|
|-id=Technetium-107
| <sup>107</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 64
| 106.9154584(93)
| 21.2(2)&nbsp;s
| β<sup>−</sup>
| <sup>107</sup>Ru
| (3/2−)
|
|-id=Technetium-107m1
| style="text-indent:1em" | <sup>107m1</sup>Tc
| colspan="3" style="text-indent:2em" | 30.1(1)&nbsp;keV
| 3.85(5)&nbsp;μs
| IT
| <sup>107</sup>Tc
| (1/2+)
|
|-id=Technetium-107m2
| style="text-indent:1em" | <sup>107m2</sup>Tc
| colspan="3" style="text-indent:2em" | 65.72(14)&nbsp;keV
| 184(3)&nbsp;ns
| IT
| <sup>107</sup>Tc
| (5/2+)
|
|-id=Technetium-108
| <sup>108</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 65
| 107.9184935(94)
| 5.17(7)&nbsp;s
| β<sup>−</sup>
| <sup>108</sup>Ru
| (2)+
|
|-id=Technetium-109
| rowspan=2|<sup>109</sup>Tc
| rowspan=2 style="text-align:right" | 43
| rowspan=2 style="text-align:right" | 66
| rowspan=2|108.920254(10)
| rowspan=2|905(21)&nbsp;ms
| β<sup>−</sup> (99.92%)
| <sup>109</sup>Ru
| rowspan=2|(5/2+)
| rowspan=2|
|-
| β<sup>−</sup>, [[neutron emission|n]] (0.08%)
| <sup>108</sup>Ru
|-id=Technetium-110
| rowspan=2|<sup>110</sup>Tc
| rowspan=2 style="text-align:right" | 43
| rowspan=2 style="text-align:right" | 67
| rowspan=2|109.923741(10)
| rowspan=2|900(13)&nbsp;ms
| β<sup>−</sup> (99.96%)
| <sup>110</sup>Ru
| rowspan=2|(2+,3+)
| rowspan=2|
|-
| β<sup>−</sup>, n (0.04%)
| <sup>109</sup>Ru
|-id=Technetium-111
| rowspan=2|<sup>111</sup>Tc
| rowspan=2 style="text-align:right" | 43
| rowspan=2 style="text-align:right" | 68
| rowspan=2|110.925899(11)
| rowspan=2|350(11)&nbsp;ms
| β<sup>−</sup> (99.15%)
| <sup>111</sup>Ru
| rowspan=2|5/2+#
| rowspan=2|
|-
| β<sup>−</sup>, n (0.85%)
| <sup>110</sup>Ru
|-id=Technetium-112
| rowspan=2|<sup>112</sup>Tc
| rowspan=2 style="text-align:right" | 43
| rowspan=2 style="text-align:right" | 69
| rowspan=2|111.9299417(59)
| rowspan=2|323(6)&nbsp;ms
| β<sup>−</sup> (98.5%)
| <sup>112</sup>Ru
| rowspan=2|(2+)
| rowspan=2|
|-
| β<sup>−</sup>, n (1.5%)
| <sup>111</sup>Ru
|-id=Technetium-112m
| style="text-indent:1em" | <sup>112m</sup>Tc
| colspan="3" style="text-indent:2em" | 352.3(7)&nbsp;keV
| 150(17)&nbsp;ns
| IT
| <sup>112</sup>Tc
| 
|
|-id=Technetium-113
| rowspan=2|<sup>113</sup>Tc
| rowspan=2 style="text-align:right" | 43
| rowspan=2 style="text-align:right" | 70
| rowspan=2|112.9325690(36)
| rowspan=2|152(8)&nbsp;ms
| β<sup>−</sup> (97.9%)
| <sup>113</sup>Ru
| rowspan=2|5/2+#
| rowspan=2|
|-
| β<sup>−</sup>, n (2.1%)
| <sup>112</sup>Ru
|-id=Technetium-113m
| style="text-indent:1em" | <sup>113m</sup>Tc
| colspan="3" style="text-indent:2em" | 114.4(5)&nbsp;keV
| 527(16)&nbsp;ns
| IT
| <sup>113</sup>Tc
| 5/2−#
|
|-id=Technetium-114
| rowspan=2|<sup>114</sup>Tc
| rowspan=2 style="text-align:right" | 43
| rowspan=2 style="text-align:right" | 71
| rowspan=2|113.93709(47)
| rowspan=2|121(9)&nbsp;ms
| β<sup>−</sup> (98.7%)
| <sup>114</sup>Ru
| rowspan=2|5+#
| rowspan=2|
|-
| β<sup>−</sup>, n (1.3%)
| <sup>113</sup>Ru
|-id=Technetium-114m
| rowspan=2 style="text-indent:1em" | <sup>114m</sup>Tc<ref group="n" name="order"/>
| rowspan=2 colspan="3" style="text-indent:2em" | 160(430)&nbsp;keV
| rowspan=2|90(20)&nbsp;ms
| β<sup>−</sup> (98.7%)
| <sup>114</sup>Ru
| rowspan=2|1+#
| rowspan=2|
|-
| β<sup>−</sup>, n (1.3%)
| <sup>113</sup>Ru
|-id=Technetium-115
| <sup>115</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 72
| 114.94010(21)#
| 78(2)&nbsp;ms
| β<sup>−</sup>
| <sup>115</sup>Ru
| 5/2+#
|
|-id=Technetium-116
| <sup>116</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 73
| 115.94502(32)#
| 57(3)&nbsp;ms
| β<sup>−</sup>
| <sup>116</sup>Ru
| 2+#
|
|-id=Technetium-117
| <sup>117</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 74
| 116.94832(43)#
| 44.5(30)&nbsp;ms
| β<sup>−</sup>
| <sup>117</sup>Ru
| 5/2+#
|
|-id=Technetium-118
| <sup>118</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 75
| 117.95353(43)#
| 30(4)&nbsp;ms
| β<sup>−</sup>
| <sup>118</sup>Ru
| 2+#
|
|-id=Technetium-119
| <sup>119</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 76
| 118.95688(54)#
| 22(3)&nbsp;ms
| β<sup>−</sup>
| <sup>119</sup>Ru
| 5/2+#
|
|-id=Technetium-120
| <sup>120</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 77
| 119.96243(54)#
| 21(5)&nbsp;ms
| β<sup>−</sup>
| <sup>120</sup>Ru
| 3+#
|
|-id=Technetium-121
| <sup>121</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 78
| 120.96614(54)#
| 22(6)&nbsp;ms
| β<sup>−</sup>
| <sup>121</sup>Ru
| 5/2+#
|
|-id=Technetium-122
| <sup>122</sup>Tc
| style="text-align:right" | 43
| style="text-align:right" | 79
| 121.97176(32)#
| 13#&nbsp;ms<br>[>550&nbsp;ns]
| 
| 
| 1+#
|
{{Isotopes table/footer}}

==Stability of technetium isotopes==
{{see also|Beta-decay stable isobars}}
Technetium and [[promethium]] are unusual light elements in that they have no stable isotopes. Using the [[liquid drop model]] for atomic nuclei, one can derive a semiempirical formula for the binding energy of a nucleus. This formula predicts a "[[valley of stability|valley of beta stability]]" along which [[nuclide]]s do not undergo beta decay. Nuclides that lie "up the walls" of the valley tend to decay by beta decay towards the center (by emitting an electron, emitting a [[positron]], or capturing an electron). For a fixed number of nucleons ''A'', the binding energies lie on one or more [[parabola]]s, with the most stable nuclide at the bottom. One can have more than one parabola because isotopes with an even number of protons and an even number of neutrons are more stable than isotopes with an odd number of neutrons and an odd number of protons. A single beta decay then transforms one into the other. When there is only one parabola, there can be only one stable isotope lying on that parabola. When there are two parabolas, that is, when the number of nucleons is even, it can happen (rarely) that there is a stable nucleus with an odd number of neutrons and an odd number of protons (although this happens only in five instances: [[deuterium|<sup>2</sup>H]], [[lithium-6|<sup>6</sup>Li]], [[boron-10|<sup>10</sup>B]], [[nitrogen-14|<sup>14</sup>N]] and [[Isotopes of tantalum#Tantalum-180m|<sup>180m</sup>Ta]]). However, if this happens, there can be no stable isotope with an even number of neutrons and an even number of protons.

For technetium (''Z''&nbsp;=&nbsp;43), the valley of beta stability is centered at around 98 nucleons. However, for every number of nucleons from 94 to 102, there is already at least one stable nuclide of either [[isotopes of molybdenum|molybdenum]] (''Z''&nbsp;=&nbsp;42) or [[isotopes of ruthenium|ruthenium]] (''Z''&nbsp;=&nbsp;44), and the [[Mattauch isobar rule]] states that two adjacent [[isobar (nuclide)|isobars]] cannot both be stable.<ref name="1syn" /> For the isotopes with odd numbers of nucleons, this immediately rules out a stable isotope of technetium, since there can be only one stable nuclide with a fixed odd number of nucleons. For the isotopes with an even number of nucleons, since technetium has an odd number of protons, any isotope must also have an odd number of neutrons. In such a case, the presence of a stable nuclide having the same number of nucleons and an even number of protons rules out the possibility of a stable nucleus.<ref name="1syn">{{cite journal |last1=Johnstone |first1=E.V. |last2=Yates |first2=M.A. |last3=Poineau |first3=F. |last4=Sattelberger |first4=A.P. |last5=Czerwinski |first5=K.R. |title=Technetium, the first radioelement on the periodic table |date=2017 |journal=Journal of Chemical Education |volume=94 |issue=3 |pages=320–326 |doi=10.1021/acs.jchemed.6b00343 |bibcode=2017JChEd..94..320J |osti=1368098 |url=https://www.osti.gov/biblio/1368098}}</ref><ref>''Radiochemistry and Nuclear Chemistry''</ref>

== See also ==
'''Daughter products other than technetium'''
* [[Isotopes of ruthenium]]
* [[Isotopes of molybdenum]]
* [[Isotopes of niobium]]

==References==
{{Reflist}}

{{Navbox element isotopes}}

[[Category:Isotopes of technetium| ]]
[[Category:Technetium]]
[[Category:Lists of isotopes by element|Technetium]]