Isotopes of phosphorus

Although phosphorus (₁₅P) has 23 isotopes from ²⁵P to ⁴⁷P, only ³¹P is stable; as such, phosphorus is considered a monoisotopic element. The longest-lived radioactive isotopes are ³³P with a half-life of 25.34 days and ³²P with a half-life of 14.268 days. All others have half-lives of under 2.5 minutes, most under a second. The least stable is ²⁵P with a half-life shorter than 30 nanoseconds.

Main isotopes of phosphorus (₁₅P)

Iso­tope Decay abun­dance half-life (t1/2) mode pro­duct ^31P 100% stable ^32P trace 14.268 d β^− ^32S ^33P trace 25.3 d β^− ^33S
Standard atomic weight Ar, standard(P)	30.973761998(5)[1]

List of isotopes

Nuclide[2] [n 1]	Z	N	Isotopic mass (Da)[3] [n 2][n 3]	Half-life [n 4]	Decay mode [n 5]	Daughter isotope [n 6]	Spin and parity [n 7][n 4]	Natural abundance (mole fraction)
	Excitation energy							Normal proportion	Range of variation
^25P	15	10	25.02119(43)#	<30 ns	p	^24Si	(1/2+)#
^26P[n 8]	15	11	26.01178(21)#	43.7(6) ms	β^+ (63.2%)	^26Si	(3+)
					β^+, p (36.8%)	^25Al
^26mP	164.4(1) keV			120(9) ns	IT	^26P
^27P	15	12	26.999224(28)	260(80) ms	β^+ (99.93%)	^27Si	1/2+
					β^+, p (.07%)	^26Al
^28P	15	13	27.9923266(12)	270.3(5) ms	β^+ (99.99%)	^28Si	3+
					β^+, p (.0013%)	^27Al
					β^+, α (8.6×10^−4%)	^24Mg
^29P	15	14	28.9818004(4)	4.142(15) s	β^+	^29Si	1/2+
^30P	15	15	29.97831349(7)	2.498(4) min	β^+	^30Si	1+
^31P	15	16	30.9737619986(7)	Stable			1/2+	1.0000
^32P	15	17	31.97390764(4)	14.268(5) d	β^−	^32S	1+	Trace
^33P	15	18	32.9717257(12)	25.35(11) d	β^−	^33S	1/2+
^34P	15	19	33.9736459(9)	12.43(10) s	β^−	^34S	1+
^35P	15	20	34.9733141(20)	47.3(8) s	β^−	^35S	1/2+
^36P	15	21	35.978260(14)	5.6(3) s	β^−	^36S	4−
^37P	15	22	36.97961(4)	2.31(13) s	β^−	^37S	(1/2+)
^38P	15	23	37.98430(8)	0.64(14) s	β^− (87.5%)	^38S
					β^−, n (12.5%)	^37S
^39P	15	24	38.98629(12)	282(24) ms	β^− (73.2%)	^39S	1/2+#
					β^−, n (26.8%)	^38S
^40P	15	25	39.99129(16)	150(8) ms	β^− (84.2%)	^40S	(2−,3−)
					β^−, n (15.8%)	^39S
^41P	15	26	40.99465(13)	101(5) ms	β^− (70%)	^41S	1/2+#
					β^−, n (30%)	^40S
^42P	15	27	42.00108(34)	48.5(15) ms	β^− (50%)	^42S
					β^−, n (50%)	^41S
^43P	15	28	43.00502(60)	35.8(13) ms	β^−, n	^42S	1/2+#
					β^−	^43S
^44P	15	29	44.01122(54)#	18.5(25) ms	β^−	^44S
^45P	15	30	45.01675(54)#	8# ms [>200 ns]	β^−	^45S	1/2+#
^46P	15	31	46.02466(75)#	4# ms [>200 ns]	β^−	^46S
^47P[4]	15	32	47.03190(86)#	2# ms	β^−	^47S

1. ^mP – Excited nuclear isomer.
2. ( ) – Uncertainty (1σ) is given in concise form in parentheses after the corresponding last digits.
3. # – Atomic mass marked #: value and uncertainty derived not from purely experimental data, but at least partly from trends from the Mass Surface (TMS).
4. # – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).
5. Modes of decay:

   IT:	Isomeric transition
   n:	Neutron emission
   p:	Proton emission

6. Bold symbol as daughter – Daughter product is stable.
7. ( ) spin value – Indicates spin with weak assignment arguments.
8. Has 1 halo proton

Radioactive isotopes

Phosphorus-32

³²P, a beta-emitter (1.71 MeV) with a half-life of 14.3 days, is used routinely in life-science laboratories, primarily to produce radiolabeled DNA and RNA probes, e.g. for use in Northern blots or Southern blots. Because the high-energy beta particles produced penetrate skin and corneas, and because any ³²P ingested, inhaled, or absorbed is readily incorporated into bone and nucleic acids, OSHA requires that a lab coat, disposable gloves, and safety glasses or goggles be worn when working with ³²P, and that working directly over an open container be avoided in order to protect the eyes. Monitoring personal, clothing, and surface contamination is also required. In addition, due to the high energy of the beta particles, shielding this radiation with the normally used dense materials (e.g. lead), gives rise to secondary emission of X-rays via a process known as bremsstrahlung, meaning braking radiation. Therefore, shielding must be accomplished with low-density materials, e.g. Plexiglas, Lucite, plastic, wood, or water.

Phosphorus-33

³³P, a beta-emitter (0.25 MeV) with a half-life of 25.4 days. It is used in life-science laboratories in applications in which lower energy beta emissions are advantageous such as DNA sequencing. ³³P can be used to label nucleotides. It is less energetic than ³²P, giving a better resolution. A disadvantage is its higher cost compared to ³²P, as most of the bombarded ³¹P will have acquired only one neutron, while only some will have acquired two or more. Its maximum specific activity is 5118 Ci/mol.

External links

• Phosphorus isotopes data from The Berkeley Laboratory Isotopes Project's

References

1. Meija, Juris; et al. (2016). "Atomic weights of the elements 2013 (IUPAC Technical Report)". Pure and Applied Chemistry. 88 (3): 265–91. doi:10.1515/pac-2015-0305.
2. Half-life, decay mode, nuclear spin, and isotopic composition is sourced in:
   Audi, G.; Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S. (2017). "The NUBASE2016 evaluation of nuclear properties" (PDF). Chinese Physics C. 41 (3): 030001. Bibcode:2017ChPhC..41c0001A. doi:10.1088/1674-1137/41/3/030001.
3. Wang, M.; Audi, G.; Kondev, F. G.; Huang, W. J.; Naimi, S.; Xu, X. (2017). "The AME2016 atomic mass evaluation (II). Tables, graphs, and references" (PDF). Chinese Physics C. 41 (3): 030003-1–030003-442. doi:10.1088/1674-1137/41/3/030003.
4. Neufcourt, L.; Cao, Y.; Nazarewicz, W.; Olsen, E.; Viens, F. (2019). "Neutron drip line in the Ca region from Bayesian model averaging". Physical Review Letters. 122: 062502–1—062502–6. arXiv:1901.07632. doi:10.1103/PhysRevLett.122.062502.