Isotopes of titanium
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Standard atomic weight Ar°(Ti) | |||||||||||||||||||||||||||||||||||||||||
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Naturally occurring titanium (22Ti) is composed of five stable isotopes; 46Ti, 47Ti, 48Ti, 49Ti and 50Ti with 48Ti being the most abundant (73.8% natural abundance). Twenty-one radioisotopes have been characterized, with the most stable being 44Ti with a half-life of 60 years, 45Ti with a half-life of 184.8 minutes, 51Ti with a half-life of 5.76 minutes, and 52Ti with a half-life of 1.7 minutes. All of the remaining radioactive isotopes have half-lives that are less than 33 seconds, and the majority of these have half-lives that are less than half a second.[4]
The isotopes of titanium range in atomic mass from 39.00 Da (39Ti) to 64.00 Da (64Ti). The primary decay mode for isotopes lighter than the stable isotopes (lighter than 46Ti) is β+ and the primary mode for the heavier ones (heavier than 50Ti) is β−; their respective decay products are scandium isotopes and the primary products after are vanadium isotopes.[4]
Two stable isotopes of titanium (47Ti and 49Ti) have non-zero nuclear spin of 5/2− and 7/2−, respectively, and thus are NMR-active.[5]
List of isotopes
[edit]
Nuclide [n 1] |
Z | N | Isotopic mass (Da)[6] [n 2][n 3] |
Half-life[1] [n 4] |
Decay mode[1] [n 5] |
Daughter isotope [n 6] |
Spin and parity[1] [n 7][n 4] |
Natural abundance (mole fraction) | |||||||||||
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Excitation energy | Normal proportion[1] | Range of variation | |||||||||||||||||
39Ti | 22 | 17 | 39.00268(22)# | 28.5(9) ms | β+, p (93.7%) | 38Ca | 3/2+# | ||||||||||||
β+ (~6.3%) | 39Sc | ||||||||||||||||||
β+, 2p (?%) | 37K | ||||||||||||||||||
40Ti | 22 | 18 | 39.990345(73) | 52.4(3) ms | β+, p (95.8%) | 39Ca | 0+ | ||||||||||||
β+ (4.2%) | 40Sc | ||||||||||||||||||
41Ti | 22 | 19 | 40.983148(30) | 81.9(5) ms | β+, p (91.1%) | 40Ca | 3/2+ | ||||||||||||
β+ (8.9%) | 41Sc | ||||||||||||||||||
42Ti | 22 | 20 | 41.97304937(29) | 208.3(4) ms | β+ | 42Sc | 0+ | ||||||||||||
43Ti | 22 | 21 | 42.9685284(61) | 509(5) ms | β+ | 43Sc | 7/2− | ||||||||||||
43m1Ti | 313.0(10) keV | 11.9(3) μs | IT | 43Ti | (3/2+) | ||||||||||||||
43m2Ti | 3066.4(10) keV | 556(6) ns | IT | 43Ti | (19/2−) | ||||||||||||||
44Ti | 22 | 22 | 43.95968994(75) | 59.1(3) y | EC | 44Sc | 0+ | ||||||||||||
45Ti | 22 | 23 | 44.95812076(90) | 184.8(5) min | β+ | 45Sc | 7/2− | ||||||||||||
45mTi | 36.53(15) keV | 3.0(2) μs | IT | 45Ti | 3/2− | ||||||||||||||
46Ti | 22 | 24 | 45.952626356(97) | Stable | 0+ | 0.0825(3) | |||||||||||||
47Ti | 22 | 25 | 46.951757491(85) | Stable | 5/2− | 0.0744(2) | |||||||||||||
48Ti | 22 | 26 | 47.947940677(79) | Stable | 0+ | 0.7372(3) | |||||||||||||
49Ti | 22 | 27 | 48.947864391(84) | Stable | 7/2− | 0.0541(2) | |||||||||||||
50Ti | 22 | 28 | 49.944785622(88) | Stable | 0+ | 0.0518(2) | |||||||||||||
51Ti | 22 | 29 | 50.94660947(52) | 5.76(1) min | β− | 51V | 3/2− | ||||||||||||
52Ti | 22 | 30 | 51.9468835(29) | 1.7(1) min | β− | 52V | 0+ | ||||||||||||
53Ti | 22 | 31 | 52.9496707(31) | 32.7(9) s | β− | 53V | (3/2)− | ||||||||||||
54Ti | 22 | 32 | 53.950892(17) | 2.1(10) s | β− | 54V | 0+ | ||||||||||||
55Ti | 22 | 33 | 54.955091(31) | 1.3(1) s | β− | 55V | (1/2)− | ||||||||||||
56Ti | 22 | 34 | 55.95768(11) | 200(5) ms | β− | 56V | 0+ | ||||||||||||
57Ti | 22 | 35 | 56.96307(22) | 95(8) ms | β− | 57V | 5/2−# | ||||||||||||
58Ti | 22 | 36 | 57.96681(20) | 55(6) ms | β− | 58V | 0+ | ||||||||||||
59Ti | 22 | 37 | 58.97222(32)# | 28.5(19) ms | β− | 59V | 5/2−# | ||||||||||||
59mTi | 108.5(5) keV | 615(11) ns | IT | 59Ti | 1/2−# | ||||||||||||||
60Ti | 22 | 38 | 59.97628(26) | 22.2(16) ms | β− | 60V | 0+ | ||||||||||||
61Ti | 22 | 39 | 60.98243(32)# | 15(4) ms | β− | 61V | 1/2−# | ||||||||||||
61m1Ti | 125.0(5) keV | 200(28) ns | IT | 61Ti | 5/2−# | ||||||||||||||
61m2Ti | 700.1(7) keV | 354(69) ns | IT | 61Ti | 9/2+# | ||||||||||||||
62Ti | 22 | 40 | 61.98690(43)# | 9# ms [>620 ns] |
0+ | ||||||||||||||
63Ti | 22 | 41 | 62.99371(54)# | 10# ms [>620 ns] |
1/2−# | ||||||||||||||
64Ti | 22 | 42 | 63.99841(64)# | 5# ms [>620 ns] |
0+ | ||||||||||||||
This table header & footer: |
- ^ mTi – Excited nuclear isomer.
- ^ ( ) – Uncertainty (1σ) is given in concise form in parentheses after the corresponding last digits.
- ^ # – Atomic mass marked #: value and uncertainty derived not from purely experimental data, but at least partly from trends from the Mass Surface (TMS).
- ^ a b # – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).
- ^
Modes of decay:
EC: Electron capture
n: Neutron emission p: Proton emission - ^ Bold symbol as daughter – Daughter product is stable.
- ^ ( ) spin value – Indicates spin with weak assignment arguments.
Titanium-44
[edit]Titanium-44 (44Ti) is a radioactive isotope of titanium that undergoes electron capture to an excited state of scandium-44 with a half-life of 60 years, before the ground state of 44Sc and ultimately 44Ca are populated.[7] Because titanium-44 can only decay through electron capture, its half-life increases with its ionization state and it becomes stable in its fully ionized state (that is, having a charge of +22).[8]
Titanium-44 is produced in relative abundance in the alpha process in stellar nucleosynthesis and the early stages of supernova explosions.[9] It is produced when calcium-40 fuses with an alpha particle (helium-4 nucleus) in a star's high-temperature environment; the resulting 44Ti nucleus can then fuse with another alpha particle to form chromium-48. The age of supernovae may be determined through measurements of gamma-ray emissions from titanium-44 and its abundance.[8] It was observed in the Cassiopeia A supernova remnant and SN 1987A at a relatively high concentration, a consequence of delayed decay resulting from ionizing conditions.[7][8]
See also
[edit]Daughter products other than titanium
References
[edit]- ^ a b c d e 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.
- ^ "Standard Atomic Weights: Titanium". CIAAW. 1993.
- ^ 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 Barbalace, Kenneth L. (2006). "Periodic Table of Elements: Ti - Titanium". Retrieved 2006-12-26.
- ^ Lucier, Bryan E.G.; Huang, Yining (2016). Reviewing 47/49Ti Solid-State NMR Spectroscopy. Annual Reports on NMR Spectroscopy. Vol. 88. pp. 1–78. doi:10.1016/bs.arnmr.2015.10.001. ISBN 978-0-12-804713-2.
- ^ 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 b Motizuki, Y.; Kumagai, S. (2004). "Radioactivity of the key isotope 44Ti in SN 1987A". AIP Conference Proceedings. 704 (1): 369–374. arXiv:astro-ph/0312620. Bibcode:2004AIPC..704..369M. doi:10.1063/1.1737130.
- ^ a b c Mochizuki, Y.; Takahashi, K.; Janka, H.-Th.; Hillebrandt, W.; Diehl, R. (2008). "Titanium-44: Its effective decay rate in young supernova remnants, and its abundance in Cas A". Astronomy and Astrophysics. 346 (3): 831–842. arXiv:astro-ph/9904378.
- ^ Fryer, C.; Dimonte, G.; Ellinger, E.; Hungerford, A.; Kares, B.; Magkotsios, G.; Rockefeller, G.; Timmes, F.; Woodward, P.; Young, P. (2011). Nucleosynthesis in the Universe, Understanding 44Ti (PDF). ADTSC Science Highlights (Report). Los Alamos National Laboratory. pp. 42–43.
- Isotope masses from:
- Audi, Georges; Bersillon, Olivier; Blachot, Jean; Wapstra, Aaldert Hendrik (2003), "The NUBASE evaluation of nuclear and decay properties", Nuclear Physics A, 729: 3–128, Bibcode:2003NuPhA.729....3A, doi:10.1016/j.nuclphysa.2003.11.001
- Isotopic compositions and standard atomic masses from:
- de Laeter, John Robert; Böhlke, John Karl; De Bièvre, Paul; Hidaka, Hiroshi; Peiser, H. Steffen; Rosman, Kevin J. R.; Taylor, Philip D. P. (2003). "Atomic weights of the elements. Review 2000 (IUPAC Technical Report)". Pure and Applied Chemistry. 75 (6): 683–800. doi:10.1351/pac200375060683.
- Wieser, Michael E. (2006). "Atomic weights of the elements 2005 (IUPAC Technical Report)". Pure and Applied Chemistry. 78 (11): 2051–2066. doi:10.1351/pac200678112051.
- "News & Notices: Standard Atomic Weights Revised". International Union of Pure and Applied Chemistry. 19 October 2005.
- Half-life, spin, and isomer data selected from the following sources.
- Audi, Georges; Bersillon, Olivier; Blachot, Jean; Wapstra, Aaldert Hendrik (2003), "The NUBASE evaluation of nuclear and decay properties", Nuclear Physics A, 729: 3–128, Bibcode:2003NuPhA.729....3A, doi:10.1016/j.nuclphysa.2003.11.001
- National Nuclear Data Center. "NuDat 2.x database". Brookhaven National Laboratory.
- Holden, Norman E. (2004). "11. Table of the Isotopes". In Lide, David R. (ed.). CRC Handbook of Chemistry and Physics (85th ed.). Boca Raton, Florida: CRC Press. ISBN 978-0-8493-0485-9.