Isotopes of praseodymium - AbsoluteAstronomy.com

Naturally occurring praseodymium
Praseodymium
Praseodymium is a chemical element that has the symbol Pr and atomic number 59. Praseodymium is a soft, silvery, malleable and ductile metal in the lanthanide group. It is too reactive to be found in native form, and when artificially prepared, it slowly develops a green oxide coating.The element...

(Pr) is composed of one stable isotope

Isotope

Isotopes are variants of atoms of a particular chemical element, which have differing numbers of neutrons. Atoms of a particular element by definition must contain the same number of protons but may have a distinct number of neutrons which differs from atom to atom, without changing the designation...

, ¹⁴¹Pr. Thirty-eight radioisotopes have been characterized with the most stable being ¹⁴³Pr with a half-life

Half-life

Half-life, abbreviated t½, is the period of time it takes for the amount of a substance undergoing decay to decrease by half. The name was originally used to describe a characteristic of unstable atoms , but it may apply to any quantity which follows a set-rate decay.The original term, dating to...

of 13.57 days and ¹⁴²Pr with a half-life of 19.12 hours. All of the remaining radioactive isotopes have half-lives that are less than 5.985 hours and the majority of these have half-lives that are less than 33 seconds. This element also has 15 meta states with the most stable being ^138mPr (t_½ 2.12 hours), ^142mPr (t_½ 14.6 minutes) and ^134mPr (t_½ 11 minutes).

The isotopes of praseodymium range in atomic weight

Atomic weight

Atomic weight is a dimensionless physical quantity, the ratio of the average mass of atoms of an element to 1/12 of the mass of an atom of carbon-12...

from 120.955 u

Atomic mass unit

The unified atomic mass unit or dalton is a unit that is used for indicating mass on an atomic or molecular scale. It is defined as one twelfth of the rest mass of an unbound neutral atom of carbon-12 in its nuclear and electronic ground state, and has a value of...

(¹²¹Pr) to 158.955 u (¹⁵⁹Pr). The primary decay mode before the stable isotope, ¹⁴¹Pr, is electron capture

Electron capture

Electron capture is a process in which a proton-rich nuclide absorbs an inner atomic electron and simultaneously emits a neutrino...

and the primary mode after is beta minus decay. The primary decay product

Decay product

In nuclear physics, a decay product is the remaining nuclide left over from radioactive decay. Radioactive decay often involves a sequence of steps...

s before ¹⁴¹Pr are element 58 (cerium

Cerium

Cerium is a chemical element with the symbol Ce and atomic number 58. It is a soft, silvery, ductile metal which easily oxidizes in air. Cerium was named after the dwarf planet . Cerium is the most abundant of the rare earth elements, making up about 0.0046% of the Earth's crust by weight...

) isotopes and the primary products after are element 60 (neodymium

Neodymium

Neodymium is a chemical element with the symbol Nd and atomic number 60. It is a soft silvery metal that tarnishes in air. Neodymium was discovered in 1885 by the Austrian chemist Carl Auer von Welsbach. It is present in significant quantities in the ore minerals monazite and bastnäsite...

) isotopes.

Standard atomic mass: 140.90765(2) u

Table

nuclide symbol	Z(p Proton The proton is a subatomic particle with the symbol or and a positive electric charge of 1 elementary charge. One or more protons are present in the nucleus of each atom, along with neutrons. The number of protons in each atom is its atomic number.... )	N(n Neutron The neutron is a subatomic hadron particle which has the symbol or , no net electric charge and a mass slightly larger than that of a proton. With the exception of hydrogen, nuclei of atoms consist of protons and neutrons, which are therefore collectively referred to as nucleons. The number of... )	isotopic mass (u)	half-life	decay mode(s)Abbreviations: EC: Electron capture Electron capture Electron capture is a process in which a proton-rich nuclide absorbs an inner atomic electron and simultaneously emits a neutrino... IT: Isomeric transition Isomeric transition An isomeric transition is a radioactive decay process that involves emission of a gamma ray from an atom where the nucleus is in an excited metastable state, referred to in its excited state, as a nuclear isomer....	daughter isotope(s)Bold for stable isotopes, bold italics for nearly-stable isotopes (half-life longer than the age of the universe Age of the universe The age of the universe is the time elapsed since the Big Bang posited by the most widely accepted scientific model of cosmology. The best current estimate of the age of the universe is 13.75 ± 0.13 billion years within the Lambda-CDM concordance model... )	nuclear spin	representative isotopic composition (mole fraction)	range of natural variation (mole fraction)
nuclide symbol	excitation energy			half-life			nuclear spin	representative isotopic composition (mole fraction)	range of natural variation (mole fraction)
¹²¹Pr	59	62	120.95536(75)#	600(300) ms	p Proton emission Proton emission is a type of radioactive decay in which a proton is ejected from a nucleus. Proton emission can occur from high-lying excited states in a nucleus following a beta decay, in which case the process is known as beta-delayed proton emission, or can occur from the ground state of very...	¹²⁰Ce	(3/2-)
					β⁺ Beta decay In nuclear physics, beta decay is a type of radioactive decay in which a beta particle is emitted from an atom. There are two types of beta decay: beta minus and beta plus. In the case of beta decay that produces an electron emission, it is referred to as beta minus , while in the case of a... (rare)	¹²¹Ce
					β⁺, p (rare)	¹²⁰La
¹²²Pr	59	63	121.95181(54)#	500# ms	β⁺	¹²²Ce
¹²³Pr	59	64	122.94596(64)#	800# ms	β⁺	¹²³Ce	3/2+#
¹²⁴Pr	59	65	123.94296(64)#	1.2(2) s	β⁺	¹²⁴Ce
¹²⁴Pr	59	65	123.94296(64)#	1.2(2) s	β⁺, p (rare)	¹²³La
¹²⁵Pr	59	66	124.93783(43)#	3.3(7) s	β⁺	¹²⁵Ce	3/2+#
¹²⁵Pr	59	66	124.93783(43)#	3.3(7) s	β⁺, p (rare)	¹²⁴La	3/2+#
¹²⁶Pr	59	67	125.93531(21)#	3.12(18) s	β⁺	¹²⁶Ce	(4,5,6)
¹²⁶Pr	59	67	125.93531(21)#	3.12(18) s	β⁺, p (rare)	¹²⁵La	(4,5,6)
¹²⁷Pr	59	68	126.93083(21)#	4.2(3) s	β⁺	¹²⁷Ce	3/2+#
^127mPr	600(200)# keV			50# ms			11/2-
¹²⁸Pr	59	69	127.92879(3)	2.84(9) s	β⁺	¹²⁸Ce	(3+)
¹²⁸Pr	59	69	127.92879(3)	2.84(9) s	β⁺, p (rare)	¹²⁷La	(3+)
¹²⁹Pr	59	70	128.92510(3)	32(3) s	β⁺	¹²⁹Ce	(11/2-)
^129mPr	382.7(5) keV			1# ms	β⁺	¹²⁹Ce	(11/2-)
¹³⁰Pr	59	71	129.92359(7)	40.0(4) s	β⁺	¹³⁰Ce	(6,7)(+#)
^130mPr	100(100)# keV			10# s			2+#
¹³¹Pr	59	72	130.92026(6)	1.50(3) min	β⁺	¹³¹Ce	(3/2+)
^131mPr	152.4(2) keV			5.7(2) s	IT Isomeric transition An isomeric transition is a radioactive decay process that involves emission of a gamma ray from an atom where the nucleus is in an excited metastable state, referred to in its excited state, as a nuclear isomer.... (96.4%)	¹³¹Pr	(11/2-)
^131mPr	152.4(2) keV			5.7(2) s	β⁺ (3.59%)	¹³¹Ce	(11/2-)
¹³²Pr	59	73	131.91926(6)	1.49(11) min	β⁺	¹³²Ce	(2+)
^132mPr	0(100)# keV			20# s	β⁺	¹³²Ce	(5+)
¹³³Pr	59	74	132.916331(13)	6.5(3) min	β⁺	¹³³Ce	(3/2+)
^133mPr	192.05(14) keV			1.1(2) µs			(11/2-)
¹³⁴Pr	59	75	133.91571(4)	~11 min	β⁺	¹³⁴Ce	(5-)
^134mPr	0(100)# keV			17(2) min	β⁺	¹³⁴Ce	2-
¹³⁵Pr	59	76	134.913112(13)	24(2) min	β⁺	¹³⁵Ce	3/2(+)
^135mPr	358.06(6) keV			105(10) µs			(11/2-)
¹³⁶Pr	59	77	135.912692(13)	13.1(1) min	β⁺	¹³⁶Ce	2+
¹³⁷Pr	59	78	136.910705(13)	1.28(3) h	β⁺	¹³⁷Ce	5/2+
^137mPr	561.22(23) keV			2.66(7) µs			11/2-
¹³⁸Pr	59	79	137.910755(15)	1.45(5) min	β⁺	¹³⁸Ce	1+
^138mPr	348(23) keV			2.12(4) h	β⁺	¹³⁸Ce	7-
¹³⁹Pr	59	80	138.908938(8)	4.41(4) h	β⁺	¹³⁹Ce	5/2+
¹⁴⁰Pr	59	81	139.909076(7)	3.39(1) min	β⁺	¹⁴⁰Ce	1+
^140m1Pr	127.5(3) keV			0.35(2) µs			5+
^140m2Pr	763.3(7) keV			3.05(20) µs			(8)-
¹⁴¹PrFission product Fission product Nuclear fission products are the atomic fragments left after a large atomic nucleus fissions. Typically, a large nucleus like that of uranium fissions by splitting into two smaller nuclei, along with a few neutrons and a large release of energy in the form of heat , gamma rays and neutrinos. The...	59	82	140.9076528(26)	Observationally StableTheoretically capable of spontaneous fission Spontaneous fission Spontaneous fission is a form of radioactive decay characteristic of very heavy isotopes. Because the nuclear binding energy reaches a maximum at a nuclear mass greater than about 60 atomic mass units , spontaneous breakdown into smaller nuclei and single particles becomes possible at heavier masses...			5/2+	1.0000
¹⁴²Pr	59	83	141.9100448(26)	19.12(4) h	β^- (99.98%)	¹⁴²Nd	2-
¹⁴²Pr	59	83	141.9100448(26)	19.12(4) h	EC Electron capture Electron capture is a process in which a proton-rich nuclide absorbs an inner atomic electron and simultaneously emits a neutrino... (.0164%)	¹⁴²Ce	2-
^142mPr	3.694(3) keV			14.6(5) min	IT	¹⁴²Pr	5-
¹⁴³Pr	59	84	142.9108169(28)	13.57(2) d	β^-	¹⁴³Nd	7/2+
¹⁴⁴Pr	59	85	143.913305(4)	17.28(5) min	β^-	*¹⁴⁴Nd*	0-
^144mPr	59.03(3) keV			7.2(3) min	IT (99.93%)	¹⁴⁴Pr	3-
^144mPr	59.03(3) keV			7.2(3) min	β^- (.07%)	*¹⁴⁴Nd*	3-
¹⁴⁵Pr	59	86	144.914512(8)	5.984(10) h	β^-	¹⁴⁵Nd	7/2+
¹⁴⁶Pr	59	87	145.91764(7)	24.15(18) min	β^-	¹⁴⁶Nd	(2)-
¹⁴⁷Pr	59	88	146.918996(25)	13.4(4) min	β^-	¹⁴⁷Nd	(3/2+)
¹⁴⁸Pr	59	89	147.922135(28)	2.29(2) min	β^-	¹⁴⁸Nd	1-
^148mPr	50(30)# keV			2.01(7) min	β^-	¹⁴⁸Nd	(4)
¹⁴⁹Pr	59	90	148.92372(9)	2.26(7) min	β^-	¹⁴⁹Nd	(5/2+)
¹⁵⁰Pr	59	91	149.926673(28)	6.19(16) s	β^-	*¹⁵⁰Nd*	(1)-
¹⁵¹Pr	59	92	150.928319(25)	18.90(7) s	β^-	¹⁵¹Nd	(3/2)(-#)
¹⁵²Pr	59	93	151.93150(13)	3.63(12) s	β^-	¹⁵²Nd	4+
¹⁵³Pr	59	94	152.93384(11)	4.28(11) s	β^-	¹⁵³Nd	5/2-#
¹⁵⁴Pr	59	95	153.93752(16)	2.3(1) s	β^-	¹⁵⁴Nd	(3+,2+)
¹⁵⁵Pr	59	96	154.94012(32)#	1# s [>300 ns]	β^-	¹⁵⁵Nd	5/2-#
¹⁵⁶Pr	59	97	155.94427(43)#	500# ms [>300 ns]	β^-	¹⁵⁶Nd
¹⁵⁷Pr	59	98	156.94743(43)#	300# ms	β^-	¹⁵⁷Nd	5/2-#
¹⁵⁸Pr	59	99	157.95198(64)#	200# ms	β^-	¹⁵⁸Nd
¹⁵⁹Pr	59	100	158.95550(75)#	100# ms	β^-	¹⁵⁹Nd	5/2-#

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