Isotopes of neon

Neon (₁₀Ne) possesses three stable isotopes: ²⁰
Ne
, ²¹
Ne
, and ²²
Ne
. In addition, 17 radioactive isotopes have been discovered, ranging from ¹⁵
Ne
to ³⁴
Ne
, all short-lived. The longest-lived is ²⁴
Ne
with a half-life of 3.38(2) min. All others are under a minute, most under a second. The least stable is ¹⁵
Ne
with a half-life of 770(300) ys (7.7(3.0)×10⁻²² s). See isotopes of carbon for notes about the measurement. Light radioactive neon isotopes usually decay to fluorine or oxygen, while heavier ones decay to sodium.

Isotopes of neon (₁₀Ne)

Main isotopes Decay abun­dance half-life (t1/2) mode pro­duct 20Ne 90.5% stable 21Ne 0.27% stable 22Ne 9.25% stable
Standard atomic weight Ar°(Ne)
	20.1797±0.0006 20.180±0.001 (abridged)

The abundances of the naturally occurring isotopes of neon

List of isotopes

Nuclide	Z	N	Isotopic mass (Da)	Half-life [resonance width]	Decay mode	Daughter isotope	Spin and parity	Natural abundance (mole fraction)
	Excitation energy							Normal proportion	Range of variation
15 Ne	10	5	15.043170(70)	770(300) ys [590(230) keV]	2p	13 O	(3/2−)
16 Ne	10	6	16.025751(22)	> 5.7 zs [< 80 keV]	2p	14 O	0+
17 Ne	10	7	17.0177140(4)	109.2(6) ms	β+p (94.4(2.9)%)	16 O	1/2−
					β+α (3.51(1)%)	13 N
					β+ (2.1(2.9)%)	17 F
					β+pα (0.014(4)%)	12 C
18 Ne	10	8	18.0057087(4)	1664.20(47) ms	β+	18 F	0+
19 Ne	10	9	19.00188091(17)	17.2569(19) s	β+	19 F	1/2+
20 Ne	10	10	19.9924401753(16)	Stable			0+	0.9048(3)	[0.8847, 0.9051]
21 Ne	10	11	20.99384669(4)	Stable			3/2+	0.0027(1)	[0.0027, 0.0171]
22 Ne	10	12	21.991385114(19)	Stable			0+	0.0925(3)	[0.0920, 0.0996]
23 Ne	10	13	22.99446691(11)	37.15(3) s	β−	23 Na	5/2+
24 Ne	10	14	23.9936106(6)	3.38(2) min	β−	24m Na	0+
25 Ne	10	15	24.997810(30)	602(8) ms	β−	25 Na	1/2+
26 Ne	10	16	26.000516(20)	197(2) ms	β− (99.87(3)%)	26 Na	0+
					β−n (0.13(3)%)	25 Na
27 Ne	10	17	27.007570(100)	30.9(1.1) ms	β− (98.0(5)%)	27 Na	(3/2+)
					β−n (2.0(5)%)	26 Na
					β−2n ?	25 Na  ?
28 Ne	10	18	28.012130(140)	18.8(2) ms	β− (84.3(1.1)%)	28 Na	0+
					β−n (12(1)%)	27 Na
					β−2n (3.7(5)%)	26 Na
29 Ne	10	19	29.019750(160)	14.7(4) ms	β− (68.0(5.1)%)	29 Na	(3/2−)
					β−n (28(5)%)	28 Na
					β−2n (4(1)%)	27 Na
30 Ne	10	20	30.024990(270)	7.22(18) ms	β− (78.1(4.6)%)	30 Na	0+
					β−n (13(4)%)	29 Na
					β−2n (8.9(2.3)%)	28 Na
31 Ne	10	21	31.033470(290)	3.4(8) ms	β−	31 Na	(3/2−)
					β−n ?	30 Na  ?
					β−2n ?	29 Na  ?
32 Ne	10	22	32.039720(540)#	3.5(9) ms	β−	32 Na	0+
					β−n ?	31 Na  ?
					β−2n ?	30 Na  ?
34 Ne	10	24	34.056730(550)#	2 ms# [> 1.5 μs]	β− ?	34 Na	0+
					β−2n ?	32 Na  ?
					β−n ?	33 Na  ?
This table header & footer:

• The isotopic composition refers to that in air.