Selenium (Se)

chemical element with symbol Se and atomic number 34

Atomic Number	34
Atomic Weight	78.971
Massagetal	80

Group	16
Period	4
Block	p

proton	34 p⁺
neutron	46 n⁰
elektron	34 e^-

Physical Property

Atoomradius	115 pm 224 pm
molar volume	16,5 cm³/mol
Covalent Radius	116 pm 107 pm 107 pm 117 pm 120 pm
Metallic Radius	117 pm 140 pm
Ioonradius	198 pm 50 pm 28 pm 42 pm
Crystal Radius	184 pm 64 pm 42 pm 56 pm
Van der Waals radius	190 pm 190 pm 403 pm 190 pm 229 pm 420,5 pm
density	4,809 g/cm³ 3 990 kg/m³

Chemical Property

energie

proton affinity
electron affinity	2,02067 eV/particle
ionization energy	9,752392 eV/particle 21,196 eV/particle 31,697 eV/particle 42,947 eV/particle 68,3 eV/particle 81,827 eV/particle 155,33 eV/particle 184 eV/particle 219 eV/particle 255 eV/particle 291 eV/particle 342,9 eV/particle 383 eV/particle 426 eV/particle 473 eV/particle 517 eV/particle 650,5 eV/particle 693,38 eV/particle 739,8 eV/particle 798 eV/particle 845,8 eV/particle 887 eV/particle 989,6 eV/particle 1 036,362 eV/particle 2 540,7 eV/particle 2 674 eV/particle 2 820 eV/particle 2 964 eV/particle 3 146 eV/particle 3 301,8 eV/particle 3 507 eV/particle 3 636,526 eV/particle 15 367,4907 eV/particle 15 968,083 eV/particle

Verdampingswarmte	59,7 kJ/mol
smeltingswarmte	5,23 kJ/mol
Vormingsentalpie	227,2 kJ/mol
elektron

Elektronskil	2, 8, 18, 6

Valenselektrone	6 ⓘ

elektronkonfigurasie	[Ar] 3d¹⁰ 4s² 4p⁴ⓘ 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁴

Oksidasietoestand	-2, -1, 0, 1, 2, 3, 4, 5, 6
Elektronegatiwiteit	14,34 eV/particle 0.2240328 2.55
Electrophilicity Index	2,2408492709619536 eV/particle
fundamental state of matter

phase of matter	Solid
gaseous state of matter
Boiling Point	958,15 K 958,15 K
Melting Point	453,15 K 493,95 K
critical pressure	27,2 MPa
critical temperature	1 766,15 K 1 766,15 K
triple point
appearance
kleur	Gray #ff1493 #ffa100 #ffa100
appearance	black, red, and gray (not pictured) allotropes
Brekingsindeks	1,000895
thermodynamic material property
Thermal Conductivity	0,52 W/(m K)
thermal expansion
molar heat capacity	25,363 J/(mol K)
Specific Heat Capacity	0,321 J/(g⋅K)
heat capacity ratio
electrical properties
type
Geleidingsvermoë
Elektriese resistiwiteit
superconductivity
Magnetisme
type	diamagnetic
magnetic susceptibility (Mass)	-0,000000004 m³/Kg
magnetic susceptibility (Molar)	-0,000000000316 m³/mol
magnetic susceptibility (Volume)	-0,0000193
magnetic ordering
Curie temperature
Néel temperature
structure
Crystal Structure	Simple Monoclinic (HEX)
lattice constant	4,36 Å
Lattice Angles	π/2, 1.58493, π/2
mechanical property
hardness	736 MPa 2 MPa
Massamodulus	8,3 GPa
Skuifmodulus	3,7 GPa
Young se modulus	10 GPa
Poisson se verhouding	0,33
Spoed van klank	3 350 m/s
classification
Category	Other nonmetals, Nonmetals
CAS Group	VIB
IUPAC Group	VIA
Glawe Number	95
Mendeleev Number	101
Pettifor Number	93
Geochemical Class	semi-volatile
Goldschmidt classification	chalcophile

other

Gas Basicity
polarizability	28,9 ± 1 a₀
C6 Dispersion Coefficient	210 a₀ 233 a₀
allotrope	Amorphous Red Selenium, Amorphous Black Selenium, Monoclinic Selenium, Hexagonal Selenium
Neutron cross section	11,7
Neutron Mass Absorption	0,0056
quantum number	3P2
Ruimtegroep	14 (P121/c1)

Isotopes of Selenium

Stable Isotopes	3
Unstable Isotopes	30
Natural Isotopes	6

⁶³Se

Massagetal	63
neutron number	29
Relative Atomic Mass	62,981911 ± 0,000537 Da
g-factor
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	13,2 ± 3,9 ms
spin	3/2
nuclear quadrupole moment
ontdekkingsdatum	2016
parity	-

decay mode	intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
β⁺ p (β⁺-delayed proton emission)	89%
2p (2-proton emission)	0.5%

⁶⁴Se

Massagetal	64
neutron number	30
Relative Atomic Mass	63,971165 ± 0,000537 Da
g-factor	0
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	22,6 ± 0,2 ms
spin	0
nuclear quadrupole moment	0
ontdekkingsdatum	2005
parity	+

decay mode	intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)
β⁺ p (β⁺-delayed proton emission)

⁶⁵Se

Massagetal	65
neutron number	31
Relative Atomic Mass	64,964552 ± 0,000322 Da
g-factor
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	34,2 ± 0,7 ms
spin	3/2
nuclear quadrupole moment
ontdekkingsdatum	1993
parity	-

decay mode	intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
β⁺ p (β⁺-delayed proton emission)	87%

⁶⁶Se

Massagetal	66
neutron number	32
Relative Atomic Mass	65,955276 ± 0,000215 Da
g-factor	0
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	54 ± 4 ms
spin	0
nuclear quadrupole moment	0
ontdekkingsdatum	1993
parity	+

decay mode	intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
β⁺ p (β⁺-delayed proton emission)

⁶⁷Se

Massagetal	67
neutron number	33
Relative Atomic Mass	66,949994 ± 0,000072 Da
g-factor
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	133 ± 4 ms
spin	5/2
nuclear quadrupole moment
ontdekkingsdatum	1991
parity	-

decay mode	intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
β⁺ p (β⁺-delayed proton emission)	0.5%

⁶⁸Se

Massagetal	68
neutron number	34
Relative Atomic Mass	67,941825236 ± 0,000000532 Da
g-factor	0
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	35,5 ± 0,7 s
spin	0
nuclear quadrupole moment	0
ontdekkingsdatum	1990
parity	+

decay mode	intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%

⁶⁹Se

Massagetal	69
neutron number	35
Relative Atomic Mass	68,939414845 ± 0,000001599 Da
g-factor
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	27,4 ± 0,2 s
spin	1/2
nuclear quadrupole moment	0
ontdekkingsdatum	1974
parity	-

decay mode	intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
β⁺ p (β⁺-delayed proton emission)	0.052%

⁷⁰Se

Massagetal	70
neutron number	36
Relative Atomic Mass	69,933515521 ± 0,0000017 Da
g-factor	0
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	41,1 ± 0,3 m
spin	0
nuclear quadrupole moment	0
ontdekkingsdatum	1950
parity	+

decay mode	intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%

⁷¹Se

Massagetal	71
neutron number	37
Relative Atomic Mass	70,932209431 ± 0,000003 Da
g-factor
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	4,74 ± 0,05 m
spin	5/2
nuclear quadrupole moment
ontdekkingsdatum	1957
parity	-

decay mode	intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%

⁷²Se

Massagetal	72
neutron number	38
Relative Atomic Mass	71,927140506 ± 0,0000021 Da
g-factor	0
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	8,4 ± 0,08 d
spin	0
nuclear quadrupole moment	0
ontdekkingsdatum	1948
parity	+

decay mode	intensity
ϵ (electron capture)	100%

⁷³Se

Massagetal	73
neutron number	39
Relative Atomic Mass	72,926754881 ± 0,000007969 Da
g-factor	0,19822222222222 ± 0,0028888888888889
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	7,15 ± 0,09 h
spin	9/2
nuclear quadrupole moment
ontdekkingsdatum	1948
parity	+

decay mode	intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%

⁷⁴Se

Massagetal	74
neutron number	40
Relative Atomic Mass	73,922475933 ± 0,000000015 Da
g-factor	0
natural abundance	0,86 ± 0,03
radioaktiwiteit	☢️ radioactive element
Halfleeftyd
spin	0
nuclear quadrupole moment	0
ontdekkingsdatum	1922
parity	+

decay mode	intensity
2β⁺ (double β⁺ decay)

⁷⁵Se

Massagetal	75
neutron number	41
Relative Atomic Mass	74,92252287 ± 0,000000078 Da
g-factor	0,2732 ± 0,004
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	119,78 ± 0,03 d
spin	5/2
nuclear quadrupole moment	1,1 ± 0,2
ontdekkingsdatum	1947
parity	+

decay mode	intensity
ϵ (electron capture)	100%

⁷⁶Se

Massagetal	76
neutron number	42
Relative Atomic Mass	75,919213702 ± 0,000000017 Da
g-factor	0
natural abundance	9,23 ± 0,07
radioaktiwiteit	Stabiele isotoop
Halfleeftyd	Not Radioactive ☢️
spin	0
nuclear quadrupole moment	0
ontdekkingsdatum	1922
parity	+

⁷⁷Se

Massagetal	77
neutron number	43
Relative Atomic Mass	76,91991415 ± 0,000000067 Da
g-factor	1,06712 ± 0,0001
natural abundance	7,6 ± 0,07
radioaktiwiteit	Stabiele isotoop
Halfleeftyd	Not Radioactive ☢️
spin	1/2
nuclear quadrupole moment	0
ontdekkingsdatum	1922
parity	-

⁷⁸Se

Massagetal	78
neutron number	44
Relative Atomic Mass	77,917309244 ± 0,000000191 Da
g-factor	0
natural abundance	23,69 ± 0,22
radioaktiwiteit	Stabiele isotoop
Halfleeftyd	Not Radioactive ☢️
spin	0
nuclear quadrupole moment	0
ontdekkingsdatum	1922
parity	+

⁷⁹Se

Massagetal	79
neutron number	45
Relative Atomic Mass	78,918499252 ± 0,000000238 Da
g-factor	-0,29085714285714 ± 0,0042857142857143
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	327 ± 28 ky
spin	7/2
nuclear quadrupole moment	0,8 ± 0,2
ontdekkingsdatum	1950
parity	+

decay mode	intensity
β⁻ (β⁻ decay)	100%

⁸⁰Se

Massagetal	80
neutron number	46
Relative Atomic Mass	79,916521761 ± 0,000001016 Da
g-factor	0
natural abundance	49,8 ± 0,36
radioaktiwiteit	☢️ radioactive element
Halfleeftyd
spin	0
nuclear quadrupole moment	0
ontdekkingsdatum	1922
parity	+

decay mode	intensity
2β⁻ (double β⁻ decay)

⁸¹Se

Massagetal	81
neutron number	47
Relative Atomic Mass	80,917993019 ± 0,000001049 Da
g-factor
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	18,45 ± 0,12 m
spin	1/2
nuclear quadrupole moment	0
ontdekkingsdatum	1948
parity	-

decay mode	intensity
β⁻ (β⁻ decay)	100%

⁸²Se

Massagetal	82
neutron number	48
Relative Atomic Mass	81,916699531 ± 0,0000005 Da
g-factor	0
natural abundance	8,82 ± 0,15
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	87,6 ± 1,5 Ey
spin	0
nuclear quadrupole moment	0
ontdekkingsdatum	1922
parity	+

decay mode	intensity
2β⁻ (double β⁻ decay)	100%

⁸³Se

Massagetal	83
neutron number	49
Relative Atomic Mass	82,919118604 ± 0,000003259 Da
g-factor
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	22,25 ± 0,04 m
spin	9/2
nuclear quadrupole moment
ontdekkingsdatum	1937
parity	+

decay mode	intensity
β⁻ (β⁻ decay)	100%

⁸⁴Se

Massagetal	84
neutron number	50
Relative Atomic Mass	83,918466761 ± 0,000002105 Da
g-factor	0
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	3,26 ± 0,1 m
spin	0
nuclear quadrupole moment	0
ontdekkingsdatum	1960
parity	+

decay mode	intensity
β⁻ (β⁻ decay)	100%

⁸⁵Se

Massagetal	85
neutron number	51
Relative Atomic Mass	84,922260758 ± 0,000002804 Da
g-factor
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	32,9 ± 0,3 s
spin	5/2
nuclear quadrupole moment
ontdekkingsdatum	1960
parity

decay mode	intensity
β⁻ (β⁻ decay)	100%

⁸⁶Se

Massagetal	86
neutron number	52
Relative Atomic Mass	85,924311732 ± 0,000002705 Da
g-factor	0
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	14,3 ± 0,3 s
spin	0
nuclear quadrupole moment	0
ontdekkingsdatum	1973
parity	+

decay mode	intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)

⁸⁷Se

Massagetal	87
neutron number	53
Relative Atomic Mass	86,928688616 ± 0,000002405 Da
g-factor
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	5,5 ± 0,06 s
spin	3/2
nuclear quadrupole moment
ontdekkingsdatum	1968
parity	+

decay mode	intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	0.6%

⁸⁸Se

Massagetal	88
neutron number	54
Relative Atomic Mass	87,93141749 ± 0,000003604 Da
g-factor	0
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	1,53 ± 0,06 s
spin	0
nuclear quadrupole moment	0
ontdekkingsdatum	1970
parity	+

decay mode	intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	0.99%

⁸⁹Se

Massagetal	89
neutron number	55
Relative Atomic Mass	88,936669058 ± 0,000004003 Da
g-factor
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	430 ± 50 ms
spin	5/2
nuclear quadrupole moment
ontdekkingsdatum	1971
parity	+

decay mode	intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	7.8%

⁹⁰Se

Massagetal	90
neutron number	56
Relative Atomic Mass	89,940096 ± 0,000354 Da
g-factor	0
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	210 ± 80 ms
spin	0
nuclear quadrupole moment	0
ontdekkingsdatum	1994
parity	+

decay mode	intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)

⁹¹Se

Massagetal	91
neutron number	57
Relative Atomic Mass	90,9457 ± 0,000465 Da
g-factor
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	270 ± 50 ms
spin	1/2
nuclear quadrupole moment	0
ontdekkingsdatum	1975
parity	+

decay mode	intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	21%
2n (2-neutron emission)

⁹²Se

Massagetal	92
neutron number	58
Relative Atomic Mass	91,94984 ± 0,000429 Da
g-factor	0
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd
spin	0
nuclear quadrupole moment	0
ontdekkingsdatum	1997
parity	+

decay mode	intensity
β⁻ (β⁻ decay)
β⁻ n (β⁻-delayed neutron emission)
2n (2-neutron emission)

⁹³Se

Massagetal	93
neutron number	59
Relative Atomic Mass	92,956135 ± 0,000429 Da
g-factor
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd
spin	1/2
nuclear quadrupole moment	0
ontdekkingsdatum	1997
parity	+

decay mode	intensity
β⁻ (β⁻ decay)
β⁻ n (β⁻-delayed neutron emission)
2n (2-neutron emission)

⁹⁴Se

Massagetal	94
neutron number	60
Relative Atomic Mass	93,96049 ± 0,000537 Da
g-factor	0
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd
spin	0
nuclear quadrupole moment	0
ontdekkingsdatum	1997
parity	+

decay mode	intensity
β⁻ (β⁻ decay)
β⁻ n (β⁻-delayed neutron emission)
2n (2-neutron emission)

⁹⁵Se

Massagetal	95
neutron number	61
Relative Atomic Mass	94,9673 ± 0,000537 Da
g-factor
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd
spin	3/2
nuclear quadrupole moment
ontdekkingsdatum	2010
parity	+

decay mode	intensity
β⁻ (β⁻ decay)
β⁻ n (β⁻-delayed neutron emission)
2n (2-neutron emission)

geskiedenis

Ontdek deur	Jöns Berzelius
ligging van ontdekking	Sweden
ontdekkingsdatum	1818
etimologie	Greek: selênê (moon).
uitspraak	si-LEE-ni-em (Engels)

source

Abundance
Abundance in Earth's crust	0,05 mg/kg
natural abundance (oseaan)	0,0002 mg/L
natural abundance (human body)	0,000005 %
natural abundance (Meteoroïde)	0,0013 %
natural abundance (Son)
Abundance in Universe	0,000003 %

Nuclear Screening Constants

1	s	0.7378
2	p	3.9348
2	s	9.1116
3	d	15.523
3	p	15.295
3	s	14.5966
4	p	25.7128
4	s	24.2424

Selenium on ChemicalAid

Art & Architecture Thesaurus ID	300156319
Australian Educational Vocabulary ID	scot/3574
BNCF	52421
BNF-kode	121383271
Biblioteca Nacional de España ID	XX534324
Brockhaus Enzyklopädie online ID	selen
CAS Registry Number	7782-49-2
ChEBI ID	27568
ChemSpider ID	4885617
DSSTOX compound identifier	DTXCID701261
DSSTox substance ID	DTXSID9021261
Den Store Danske ID	selen
DrugBank ID	11135
ECHA Substance Infocard ID	100.029.052
Encyclopædia Britannica Online ID	science/selenium
Encyclopædia Universalis ID	selenium
Freebase-kode	/m/025sf8g
French Vikidia ID	Sélénium
GND ID	4180872-1
Gran Enciclopèdia Catalana ID	0238414
Great Russian Encyclopedia Online ID	3546300
HCIS ID	4102
HSDB ID	4493
Human Metabolome Database ID	HMDB0001349
ICSC ID	0072
InChI	InChI=1S/Se
InChIKey	BUGBHKTXTAQXES-UHFFFAOYSA-N
KBpedia ID	Selenium
KEGG ID	C01529
LCCN	sh85119688
MeSH descriptor ID	D012643
NALT ID	33437
NCI Drug Dictionary ID	selenium
NDF-RT ID	N0000148196
NDL-kode	00570819
NKC-kode	ph127055
National Library of Israel J9U ID	987007529471405171
OmegaWiki Defined Meaning	3373
OpenAlex ID	C553756173
PSH ID	5808
PatientsLikeMe treatment ID	selenium
Probes And Drugs ID	PD056990
PubChem CID	6326970
Quora topic ID	Selenium-2
Quora topic ID	Selenium-element
RxNorm ID	9641
Store medisinske leksikon ID	selen
Store norske leksikon ID	selen
Treccani ID	selenio
UK Archival Thesaurus ID	f2/mt225/4347/9119
UMLS CUI	C0036581
UNII	H6241UJ22B
USGS Thesaurus ID	1572
WikiSkripta ID	12122
Wolfram Language entity code	Entity["Mineral", "Selenium"]
WordNet 3.1 Synset ID	14678354-n
YSO ID	10413
ZVG number	7340

Selenium (Se)

Physical Property

Chemical Property

other

Isotopes of Selenium

63Se

64Se

65Se

66Se

67Se

68Se

69Se

70Se

71Se

72Se

73Se

74Se

75Se

76Se

77Se

78Se

79Se

80Se

81Se

82Se

83Se

84Se

85Se

86Se

87Se

88Se

89Se

90Se

91Se

92Se

93Se

94Se

95Se

geskiedenis

source

Nuclear Screening Constants

⁶³Se

⁶⁴Se

⁶⁵Se

⁶⁶Se

⁶⁷Se

⁶⁸Se

⁶⁹Se

⁷⁰Se

⁷¹Se

⁷²Se

⁷³Se

⁷⁴Se

⁷⁵Se

⁷⁶Se

⁷⁷Se

⁷⁸Se

⁷⁹Se

⁸⁰Se

⁸¹Se

⁸²Se

⁸³Se

⁸⁴Se

⁸⁵Se

⁸⁶Se

⁸⁷Se

⁸⁸Se

⁸⁹Se

⁹⁰Se

⁹¹Se

⁹²Se

⁹³Se

⁹⁴Se

⁹⁵Se