Sb 51

Antimony (Sb)

metalloid
Period: 5 Group: 15 Block: p

Solid

Standard Atomic Weight

121.76 u

Electron configuration

[Kr] 5s2 4d10 5p3

Melting point

630.63 °C (903.78 K)

Boiling point

1586.85 °C (1860 K)

Density

6685 kg/m³

Oxidation states

−3, −2, −1, 0, +1, +2, +3, +4, +5

Electronegativity (Pauling)

2.05

Ionization energy (1st)

Discovery year

1707

Atomic radius

145 pm

Details

Name origin Greek: anti and monos (not alone); symbol from mineral stibnite.
Discoverers Known to the ancients.

Antimony is a brittle p-block metalloid in group 15. It commonly shows oxidation states +3 and +5, with chemistry that bridges arsenic and bismuth. The element is best known as a hardening additive for lead alloys and as a component of flame-retardant systems through antimony trioxide. Natural antimony is usually encountered in sulfide minerals rather than as native metal.

Antimony is a poor conductor of heat and electricity. Antimony and many of its compounds are toxic.

The name derives from the Greek, anti + monos for "not alone" or "not one" because it was found in many compounds. The symbol Sb comes from stibium, which is derived from the Greek stibi for "mark" because it was used for blackening eyebrows and eyelashes. The minerals stibnite (Sb2S3) and stibine (SbH3) are two of more than one hundred mineral species, which were known in the ancient world.

Antimony has been known since ancient times. It is sometimes found free in nature, but is usually obtained from the ores stibnite (Sb2S3) and valentinite (Sb2O3). Nicolas Lémery, a French chemist, was the first person to scientifically study antimony and its compounds. He published his findings in 1707. Antimony makes up about 0.00002% of the earth's crust.

From the Greek word anti plus monos - "a metal not found alone". Antimony was recognized in compounds by the ancients and was known as a metal at the beginning of the 17th century and possibly much earlier.

Images

Properties

Physical

Atomic radius (empirical) 145 pm
Covalent radius 139 pm
Van der Waals radius 206 pm
Metallic radius 139 pm
Density
Molar volume 0.0184 L/mol
Phase at STP solid
Melting point 630.63 °C
Boiling point 1586.85 °C
Thermal conductivity 24.43 W/(m·K)
Specific heat capacity 0.207 J/(g·K)
Molar heat capacity 25.23 J/(mol·K)
Crystal structure rhombohedral

Chemical

Electronegativity (Pauling) 2.05
Electronegativity (Allen) 1.984
Electron affinity
Ionization energy (1st)
Ionization energy (2nd)
Ionization energy (3rd)
Ionization energy (4th)
Ionization energy (5th)
Oxidation states −3, −2, −1, 0, +1, +2, +3, +4, +5
Valence electrons 5
Allotropes ["gray"]
Electron configuration
Electron configuration (semantic)

Thermodynamic

Heat of fusion 0.20417682 eV
Heat of vaporization 0.70477276 eV
Heat of sublimation 2.02104 eV
Heat of atomization 2.715448 eV
Atomization enthalpy

Nuclear

Stable isotopes 2
Discovery year 1707

Abundance

Abundance (Earth's crust) 0.2 mg/kg
Abundance (ocean)

Reactivity

N/A

Crystal Structure

Lattice constant a 451 pm

Electronic Structure

Electrons per shell 2, 8, 18, 18, 5

Identifiers

CAS number 7440-36-0
Term symbol
InChI InChI=1S/Sb
InChI Key WATWJIUSRGPENY-UHFFFAOYSA-N

Electron Configuration Measured

Ion charge
Protons 51
Electrons 51
Charge Neutral
Configuration Sb: 4d¹⁰ 5s² 5p³
Electron configuration
Measured
[Kr] 4d¹⁰ 5s² 5p³
1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p³
Orbital diagram
1s
2/2
2s
2/2
2p
6/6
3s
2/2
3p
6/6
4s
2/2
3d
10/10
4p
6/6
5s
2/2
4d
10/10
5p
3/6 3↑
Total electrons: 51 Unpaired: 3 ?

Atomic model

Protons 51
Neutrons 70
Electrons 51
Mass number 121
Stability Stable

Isotopes change neutron count, mass, and stability — not the electron configuration of a neutral atom.

Schematic atomic model, not to scale.

Atomic Fingerprint

Emission / Absorption Spectrum

8 / 8 (3 with intensity)
Measured
Emission Visible: 380–750 nm

Isotope Distribution

12157.2100%12342.7900%Mass numberNatural abundance (%)
Mass numberAtomic mass (u)Natural abundanceHalf-life
121 Stable120.903812 ± 0.00000357.2100%Stable
123 Stable122.9042132 ± 0.000002342.7900%Stable
Measured

Phase / State

1 atm / 101.325 kPa
Solid 25 °C (298.15 K)

Reason: 605.6 °C below melting point (630.63 °C)

Melting point 630.63 °C
Boiling point 1586.85 °C
Below melting by 605.6 °C
0 K Current temperature: 25 °C 6000 K
Phase timeline

Schematic, not to scale

Solid
Liquid
Gas
Melting
Boiling
25°C
Solid
Liquid
Gas
Current

Phase transition points

Melting point Literature
630.63 °C
Boiling point Literature
1586.85 °C
Current phase Calculated
Solid

Transition energies

Heat of fusion Literature
0.20417682 eV

Energy required to melt 1 mol at melting point

Heat of vaporization Literature
0.70477276 eV

Energy required to vaporize 1 mol at boiling point

Heat of sublimation Literature
2.02104 eV

Energy required to sublime 1 mol at sublimation point

Density

Reference density Literature
6685 kg/m³

At standard conditions

Current density Calculated
6685 kg/m³

At standard conditions

Atomic Spectra

Showing 10 of 51 Atomic Spectra. Sorted by ion charge (ascending).

Lines Holdings ?

IonChargeTotal linesTransition probabilitiesLevel designations
Sb I 013510128
Sb II +190261
Sb III +26100
Sb IV +31400
Sb V +4800
NIST Lines Holdings →

Levels Holdings ?

IonChargeLevels
Sb I 0153
Sb II +1110
Sb III +224
Sb IV +329
Sb V +49
Sb VI +560
Sb VII +62
Sb VIII +72
Sb IX +82
Sb X +92
NIST Levels Holdings →
51 Sb 121.76

Antimony — Atomic Orbital Visualizer

[Kr]5s24d105p3
Energy levels 2 8 18 18 5
Oxidation states -3, -2, -1, 0, +1, +2, +3, +4, +5
HOMO 5p n=5 · l=1 · m=-1
Antimony — Atomic Orbital Visualizer Preview
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51 Sb 121.76

Antimony — Crystal Structure Visualizer

Trigonal · Pearson N/A
Experimental
Pearson N/A
Antimony — Crystal Structure Visualizer Preview
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Ionic Radii

ChargeCoordinationSpinRadius
+34N/A76 pm
+35N/A80 pm
+36N/A76 pm
+56N/A60 pm

Compounds

Sb
121.760 u
Sb+3
121.760 u
Sb+5
121.760 u
Sb
124.905 u
Sb
123.906 u
Sb
116.905 u
Sb
118.904 u
Sb
120.904 u
Sb
126.907 u
Sb
121.905 u
Sb
128.909 u
Sb
119.905 u
Sb
130.912 u
Sb
125.907 u
Sb
129.912 u
Sb
122.904 u
Sb
115.907 u
Sb
127.909 u
Sb
114.907 u
Sb
117.906 u
Sb+3
125.907 u
Sb+3
126.907 u

Isotopes (2)

Mass numberAtomic mass (u)Natural abundanceHalf-lifeDecay mode
121 Stable120.903812 ± 0.00000357.2100% ± 0.0500%Stable
stable
123 Stable122.9042132 ± 0.000002342.7900% ± 0.0500%Stable
stable
121 Stable
Atomic mass (u) 120.903812 ± 0.000003
Natural abundance 57.2100% ± 0.0500%
Half-life Stable
Decay mode
stable
123 Stable
Atomic mass (u) 122.9042132 ± 0.0000023
Natural abundance 42.7900% ± 0.0500%
Half-life Stable
Decay mode
stable

Spectral Lines

Wavelength (nm)IntensityIon stageTypeTransitionAccuracySource
403.35367 nm200Sb Iemission5p3 2P* → 5p2.(3P).6s 4PMeasuredNIST
475.77494 nm20Sb Iemission5p2.(3P).6s 4P → 5p2.(3P<2>).7p (2,3/2)*MeasuredNIST
549.02252 nmN/ASb Iemission5p2.(3P).6s 4P → 5p2.(3P<2>).7p (2,1/2)*MeasuredNIST
555.60108 nmN/ASb Iemission5p2.(3P).6s 2P → 5p2.(1D<2>).6p (2,1/2)*MeasuredNIST
560.20647 nmN/ASb Iemission5p2.(3P).6s 4P → 5p2.(3P<1>).7p (1,3/2)*MeasuredNIST
563.19352 nmN/ASb Iemission5p2.(3P).6s 4P → 5p2.(3P<0>).7p (0,3/2)*MeasuredNIST
573.02392 nmN/ASb Iemission5p2.(3P).6s 2P → 5p2.(3P<2>).7p (2,3/2)*MeasuredNIST
661.1381 nm20Sb Iemission5p2.(3P).6s 2P → 5p2.(1D<2>).6p (2,1/2)*MeasuredNIST

Extended Properties

Covalent Radii (Extended)

Covalent radius (Pyykkö)  
Covalent radius (Pyykkö, double)  
Covalent radius (Pyykkö, triple)  
Covalent radius (Bragg)  

Van der Waals Radii

Truhlar  
Batsanov  
Alvarez  
UFF  
MM3  
Dreiding  

Atomic & Metallic Radii

Atomic radius (Rahm)  
Metallic radius (C12)  

Numbering Scales

Mendeleev
Pettifor
Glawe

Electronegativity Scales

Ghosh
Miedema
Gunnarsson–Lundqvist
Robles–Bartolotti

Polarizability & Dispersion

Dipole polarizability  
Dipole polarizability (unc.)  
C₆  
C₆ (Gould–Bučko)  

Miedema Parameters

Miedema molar volume  
Miedema electron density

Supply Risk & Economics

Production concentration
Relative supply risk
Reserve distribution
Political stability (top producer)
Political stability (top reserve)

Phase Transitions & Allotropes

gray
Melting point903.78 K
Boiling point1860.15 K

Oxidation State Categories

+1 extended
−1 extended
−2 extended
+5 main
+3 main
+2 extended
+4 extended
0 extended
−3 main

Advanced Reference Data

Screening Constants (11)
nOrbitalσ
1s1.0256
2p4.1274
2s13.4046
3d14.2002
3p17.8161
3s17.7909
4d32.0256
4p28.8188
4s27.4564
5p41.0055
Crystal Radii Detail (4)
ChargeCNSpinrcrystal (pm)Origin
3IVPY90
3V94
3VI90Ahrens (1952) ionic radius,
5VI74
Isotope Decay Modes (61)
IsotopeModeIntensity
102p
103p
104B+
104B+p7%
104p7%
104A
105B+100%
105p0.1%
105B+p
106B+100%
X‑ray Scattering Factors (508)
Energy (eV)f₁f₂
109.95091
10.161710.0681
10.32619.92927
10.49319.42377
10.66288.92685
10.83538.35287
11.01067.84004
11.18867.4678
11.36967.10503
11.55356.73907

Additional Data

Sources

Sources of this element.

Antimony is not abundant, but is found in over 100 mineral species. It is sometimes found natively, but more frequently it is found as the sulfide stibnite.

References (1)

References

(9)
2 Atomic Mass Data Center (AMDC), International Atomic Energy Agency (IAEA)
Sb

The half-life and atomic mass data was provided by the Atomic Mass Data Center at the International Atomic Energy Agency.

3 IUPAC Commission on Isotopic Abundances and Atomic Weights (CIAAW)
Antimony

Element data are cited from the Atomic weights of the elements (an IUPAC Technical Report). The IUPAC periodic table of elements can be found at https://iupac.org/what-we-do/periodic-table-of-elements/. Additional information can be found within IUPAC publication doi:10.1515/pac-2015-0703 Copyright © 2020 International Union of Pure and Applied Chemistry.

4 IUPAC Periodic Table of the Elements and Isotopes (IPTEI)

The information are cited from Pure Appl. Chem. 2018; 90(12): 1833-2092, https://doi.org/10.1515/pac-2015-0703.

License note: Copyright (c) 2020 International Union of Pure and Applied Chemistry. The International Union of Pure and Applied Chemistry (IUPAC) contribution within Pubchem is provided under a CC-BY-NC-ND 4.0 license, unless otherwise stated.
5 Jefferson Lab, U.S. Department of Energy
Antimony

Thomas Jefferson National Accelerator Facility (Jefferson Lab) is one of 17 national laboratories funded by the U.S. Department of Energy. The lab's primary mission is to conduct basic research of the atom's nucleus using the lab's unique particle accelerator, known as the Continuous Electron Beam Accelerator Facility (CEBAF). For more information visit https://www.jlab.org/

License note: Please see citation and linking information: https://education.jlab.org/faq/index.html
6 Los Alamos National Laboratory, U.S. Department of Energy
Antimony

The periodic table at the LANL (Los Alamos National Laboratory) contains basic element information together with the history, source, properties, use, handling and more. The provenance data may be found from the link under the source name.

7 NIST Physical Measurement Laboratory
Antimony

The periodic table contains NIST's critically-evaluated data on atomic properties of the elements. The provenance data that include data for atomic spectroscopy, X-ray and gamma ray, radiation dosimetry, nuclear physics, and condensed matter physics may be found from the link under the source name. Ref: https://www.nist.gov/pml/atomic-spectra-database

8 PubChem Elements
Antimony

This section provides all form of data related to element Antimony.

9 PubChem Elements
Antimony

The element property data was retrieved from publications.

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