Pt 78

Platinum (Pt)

transition-metal

Period: 6 Group: 10 Block: s

Solid

Standard Atomic Weight

Electron configuration

[Xe] 6s¹ 4f¹⁴ 5d⁹

Melting point

1768.4 °C (2041.55 K)

Boiling point

3824.85 °C (4098 K)

Density

2.146000e+4 kg/m³

Oxidation states

−3, −2, −1, 0, +1, +2, +3, +4, +5, +6

Electronegativity (Pauling)

2.28

Ionization energy (1st)

Discovery year

1735

Atomic radius

135 pm

Details

Name origin Spanish: platina (little silver).

Discovery country Italy

Discoverers Julius Scaliger

Platinum is a dense, silvery-white transition metal in group 10 and a member of the platinum-group elements. It is exceptionally resistant to corrosion and oxidation, yet it can catalyze many reactions at its surface. The metal is chemically noble in bulk but forms well-defined complexes, especially in the +2 and +4 oxidation states. Its combination of durability, catalytic activity, and electrical stability gives it technological importance disproportionate to its crustal abundance.

Platinum is a beautiful silvery-white metal, when pure, and is malleable and ductile. It has a coefficient of expansion almost equal to that of soda-lime-silica glass, and is therefore used to make sealed electrodes in glass systems. The metal does not oxidize in air at any temperature, but is corroded by halogens, cyanides, sulfur, and caustic alkalis.

It is insoluble in hydrochloric and nitric acid, but dissolves when they are mixed as aqua regia, forming chloroplatinic acid.

The name derives from the Spanish platina for "silver". In 1735, the Spanish astronomer Antonio de Ulloa found platinum in Peru, South America. In 1741, the English metallurgist Charles Wood found platinum from Colombia, South America. In 1750, the English physician William Brownrigg prepared purified platinum metal.

Used by the pre-Columbian Indians of South America, platinum wasn't noticed by western scientists until 1735. Platinum can occur free in nature and is sometimes found in deposits of gold-bearing sands, primarily those found in the Ural mountains, Columbia and the western United States. Platinum, in the form of the mineral sperrylite (PtAs2), is also obtained as a byproduct of the nickel mining operation in the Sudbury region of Ontario, Canada. Credit for the modern rediscovery of platinum is usually given to Antonio de Ulloa.

Discovered in South America by Ulloa in 1735 and by Wood in 1741. The metal was used by pre-Columbian Indians.

Read about Platinum on Wikipedia

Images

Properties

Physical

Atomic radius (empirical) 135 pm

Covalent radius 136 pm

Van der Waals radius 209 pm

Metallic radius 130 pm

Density

Molar volume 0.0091 L/mol

Phase at STP solid

Melting point 1768.4 °C

Boiling point 3824.85 °C

Thermal conductivity 71.6 W/(m·K)

Specific heat capacity 0.133 J/(g·K)

Molar heat capacity 25.86 J/(mol·K)

Crystal structure fcc

Chemical

Electronegativity (Pauling) 2.28

Electronegativity (Allen) 1.72

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, +6

Valence electrons 10

Electron configuration

Electron configuration (semantic)

Thermodynamic

Heat of fusion 0.20490232 eV

Heat of vaporization 4.860859 eV

Heat of sublimation 5.845468 eV

Heat of atomization 5.845468 eV

Atomization enthalpy

Nuclear

Stable isotopes 5

Discovery year 1735

Abundance

Abundance (Earth's crust) 0.005 mg/kg

Reactivity

N/A

Crystal Structure

Lattice constant a 392 pm

Electronic Structure

Electrons per shell 2, 8, 18, 32, 17, 1

Identifiers

CAS number 7440-06-4

Term symbol

InChI InChI=1S/Pt

InChI Key BASFCYQUMIYNBI-UHFFFAOYSA-N

Electron Configuration Measured

Ion charge

Protons 78

Electrons 78

Charge Neutral

Configuration Pt: 4f¹⁴ 5d⁹ 6s¹

[Xe] 4f¹⁴ 5d⁹ 6s¹

1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 4f¹⁴ 5d⁹ 6s¹

Orbital diagram

↑↓

2/2

↑↓

2/2

↑↓

6/6

↑↓

2/2

↑↓

6/6

↑↓

2/2

↑↓

10/10

↑↓

6/6

↑↓

2/2

↑↓

10/10

↑↓

6/6

↑

1/2 1↑

↑↓

14/14

↑↓

↑

9/10 1↑

Total electrons: 78 Unpaired: 2

Atomic model

Protons 78

Neutrons 116

Electrons 78

Mass number 194

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

Emission Visible: 380–750 nm

Isotope Distribution

Mass number	Atomic mass (u)	Natural abundance	Half-life
194 Stable	193.9626809 ± 0.000001	32.8600%	Stable
196 Stable	195.96495209 ± 0.00000099	25.2100%	Stable
198 Stable	197.9678949 ± 0.0000023	7.3560%	Stable

Measured

Phase / State

Solid 25 °C (298.15 K)

Reason: 1743.4 °C below melting point (1768.4 °C)

Melting point 1768.4 °C

Boiling point 3824.85 °C

Below melting by 1743.4 °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

1768.4 °C

Boiling point Literature

3824.85 °C

Current phase Calculated
Solid

Transition energies

Heat of fusion Literature

0.20490232 eV

Energy required to melt 1 mol at melting point

Heat of vaporization Literature

4.860859 eV

Energy required to vaporize 1 mol at boiling point

Heat of sublimation Literature

5.845468 eV

Energy required to sublime 1 mol at sublimation point

Density

Reference density Literature

2.146000e+4 kg/m³

At standard conditions

Current density Calculated

2.146000e+4 kg/m³

At standard conditions

Atomic Spectra

Showing 10 of 78 Atomic Spectra. Sorted by ion charge (ascending).

Lines Holdings ?

Ion	Charge	Total lines	Transition probabilities	Level designations
Pt I	0	995	166	995
Pt II	+1	2268	183	2268
Pt IV	+3	1531	1531	1531
Pt V	+4	1729	1729	1729
Pt VI	+5	1467	1467	1467
Pt VII	+6	786	786	786
Pt VIII	+7	360	360	360

NIST Lines Holdings →

Levels Holdings ?

Ion	Charge	Levels
Pt I	0	202
Pt II	+1	282
Pt III	+2	2
Pt IV	+3	238
Pt V	+4	259
Pt VI	+5	251
Pt VII	+6	178
Pt VIII	+7	80
Pt IX	+8	2
Pt X	+9	2

NIST Levels Holdings →

78 Pt 195.084

Platinum — Atomic Orbital Visualizer

[Xe]6s14f145d9

Energy levels 2 8 18 32 17 1

Oxidation states -3, -2, -1, 0, +1, +2, +3, +4, +5, +6

HOMO 6s n=6 · l=0 · m=0

Platinum — Atomic Orbital Visualizer Preview

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78 Pt 195.084

Platinum — Crystal Structure Visualizer

Face-Centered Cubic · Pearson cF4

Experimental

Pearson cF4

Coord. № 12

Packing 74.000%

Platinum — Crystal Structure Visualizer Preview

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Ionic Radii

Charge	Coordination	Spin	Radius
+2	4	N/A	60 pm
+2	6	N/A	80 pm
+4	6	N/A	62.5 pm
+5	6	N/A	56.99999999999999 pm

Compounds

195.080 u

Pt+2

195.080 u

Pt+4

195.080 u

190.962 u

194.965 u

198.971 u

192.963 u

187.959 u

185.959 u

196.967 u

199.971 u

188.961 u

Pt+4

194.965 u

Isotopes (3)

Mass number	Atomic mass (u)	Natural abundance	Half-life	Decay mode
194 Stable	193.9626809 ± 0.000001	32.8600% ± 0.4000%	Stable	stable
196 Stable	195.96495209 ± 0.00000099	25.2100% ± 0.3400%	Stable	stable
198 Stable	197.9678949 ± 0.0000023	7.3560% ± 0.1300%	Stable	stable

194 Stable

Atomic mass (u) 193.9626809 ± 0.000001

Natural abundance 32.8600% ± 0.4000%

Half-life Stable

Decay mode

stable

196 Stable

Atomic mass (u) 195.96495209 ± 0.00000099

Natural abundance 25.2100% ± 0.3400%

Half-life Stable

Decay mode

stable

198 Stable

Atomic mass (u) 197.9678949 ± 0.0000023

Natural abundance 7.3560% ± 0.1300%

Half-life Stable

Decay mode

stable

Spectral Lines

Showing 50 of 264 Spectral Lines. Only spectral lines with measured intensity are shown by default.

Wavelength (nm)	Intensity	Ion stage	Type	Transition	Accuracy	Source
381.86875 nm	8300	Pt I	emission	5d8.6s2 3F → 5d8.6s.(4F).6p a 5G*	Measured	NIST
676.00069 nm	6500	Pt I	emission	5d9.6p 3F* → 5d9.7s 3D	Measured	NIST
530.10143 nm	3900	Pt I	emission	5d8.6s.(4F).6p 5G* → 5d8.(3F<4>).6s.7s.(3S<1>) (4,1)	Measured	NIST
396.6357 nm	3400	Pt I	emission	5d8.6s2 3F → 5d8.6s.(4F).6p a 5D*	Measured	NIST
416.45502 nm	3300	Pt I	emission	5d8.6s2 3F → 5d9.6p 3F*	Measured	NIST
411.86745 nm	3000	Pt I	emission	5d9.6s b 1D → 5d9.6p 3D*	Measured	NIST
652.34376 nm	3000	Pt I	emission	5d9.6p b 3P* → 5d9.7s 1D	Measured	NIST
444.25477 nm	2400	Pt I	emission	5d8.6s2 3F → 5d9.6p a 3P*	Measured	NIST
432.70524 nm	2300	Pt I	emission	5d8.6s.(4F).6p a 5F* → 5d8.(3F<4>).6s.7s.(3S<1>) (4,1)	Measured	NIST
709.475 nm	2300	Pt I	emission	5d8.6s.(4F).6p 3G* → 5d8.(3F<4>).6s.7s.(1S<0>) (4,0)	Measured	NIST
711.37244 nm	2300	Pt I	emission	5d8.6s2 3P → 5d9.6p a 3P*	Measured	NIST
671.03998 nm	2200	Pt I	emission	5d9.6p 3D* → 5d9.7s 1D	Measured	NIST
522.76459 nm	2100	Pt I	emission	5d9.6s b 1D → 5d9.6p a 3P*	Measured	NIST
505.94815 nm	1900	Pt I	emission	5d9.6p a 3P* → 5d9.7s 3D	Measured	NIST
547.57631 nm	1900	Pt I	emission	5d9.6p 3F* → 5d9.7s 3D	Measured	NIST
584.01269 nm	1800	Pt I	emission	5d8.6s2 3F → 5d9.6p a 3P*	Measured	NIST
419.24241 nm	1700	Pt I	emission	5d9.6s b 1D → 5d9.6p b 3P*	Measured	NIST
547.84793 nm	1500	Pt I	emission	5d8.6s.(4F).6p b 5F* → 5d8.(3F<4>).6s.7s.(3S<1>) (4,1)	Measured	NIST
684.25984 nm	1500	Pt I	emission	5d9.6p 3D* → 5d9.7s 3D	Measured	NIST
449.8748 nm	1100	Pt I	emission	5d9.6p 3F* → 5d9.6d 3G	Measured	NIST
539.07754 nm	1100	Pt I	emission	5d9.6p 3F* → 5d9.7s 1D	Measured	NIST
632.6577 nm	1100	Pt I	emission	5d8.6s2 1G → 5d9.6p 3D*	Measured	NIST
584.48054 nm	1000	Pt I	emission	5d8.6s.(4F).6p b 5F* → 5d8.(3F<4>).6s.7s.(3S<1>) (4,1)	Measured	NIST
536.89866 nm	960	Pt I	emission	5d8.6s2 3F → 5d9.6p 3F*	Measured	NIST
631.83662 nm	930	Pt I	emission	5d9.6p 3P* → 5d9.7s 1D	Measured	NIST
602.60247 nm	860	Pt I	emission	5d8.6s.(4F).6p 5F* → 5d8.(3F<4>).6s.7s.(3S<1>) (4,1)	Measured	NIST
695.7507 nm	800	Pt I	emission	5d8.6s.(2F).6p a 3F* → 5d8.(3F<4>).6s.6d b (4,?)	Measured	NIST
455.24119 nm	730	Pt I	emission	5d8.6s.(4F).6p a 5F* → 5d8.(3F<4>).6s.7s.(3S<1>) (4,1)	Measured	NIST
428.80508 nm	680	Pt I	emission	5d8.6s2 3F → 5d8.6s.(2D).6p a 3F*	Measured	NIST
713.16333 nm	650	Pt I	emission	5d8.6s.(2F).6p b 3D* → 5d9.7s 3D	Measured	NIST
689.67056 nm	590	Pt I	emission	5d8.6s.(2F).6p a 3F* → 5d8.(3F<3>).6s.7s.(3S<1>) (3,1)	Measured	NIST
409.22515 nm	580	Pt I	emission	5d8.6s.(4F).6p a 5D* → 5d9.6d a 3G	Measured	NIST
707.8062 nm	580	Pt I	emission	5d8.6s.(4F).6p b 5D* → 5d8.(3F<4>).6s.7s.(3S<1>) (4,1)	Measured	NIST
401.37143 nm	570	Pt II	emission	5d8.6p 76610* → 5d8.(3P).7s (2,1/2)	Measured	NIST
628.34779 nm	570	Pt I	emission	5d8.6s.(2F).6p a 3D* → 5d9.7s 3D	Measured	NIST
683.80564 nm	560	Pt I	emission	5d9.6p 3F* → 5d8.(3F<4>).6s.7s.(3S<1>) (4,1)	Measured	NIST
452.29919 nm	550	Pt I	emission	5d9.6p 3D* → 5d9.6d 1F	Measured	NIST
664.83039 nm	550	Pt I	emission	5d9.6p b 3P* → 5d9.7s 3D	Measured	NIST
703.00606 nm	540	Pt I	emission	5d8.6s.(4P).6p a 5D* → 5d9.7s 3D	Measured	NIST
448.46871 nm	520	Pt I	emission	5d9.6p 3F* → 5d9.6d 3F	Measured	NIST
748.60309 nm	520	Pt I	emission	5d8.6s2 1G → 5d8.6s.(4F).6p a 5D*	Measured	NIST
576.3566 nm	510	Pt I	emission	5d8.6s.(4F).6p a 5D* → 5d9.7s 1D	Measured	NIST
712.5028 nm	500	Pt I	emission	5d7.(4F).6s2.6p a 3G* → 5d8.(3F<4>).6s.6d b (4,?)	Measured	NIST
427.3898 nm	490	Pt I	emission	5d8.6s.(2F).6p a 3D* → 5d9.6d b 3G	Measured	NIST
439.18207 nm	490	Pt I	emission	5d8.6s2 1G → 5d8.6s.(2F).6p a 3D*	Measured	NIST
392.53348 nm	480	Pt I	emission	5d8.6s2 3F → 5d8.6s.(4F).6p 5G*	Measured	NIST
712.2889 nm	480	Pt I	emission	5d8.6s.(4P).6p 5D* → 5d9.7d 3P	Measured	NIST
386.84222 nm	470	Pt I	emission	5d8.6s.(4F).6p b 5F* → 5d8.(3F<4>).6s.6d b (4,?)	Measured	NIST
387.57161 nm	470	Pt I	emission	5d8.6s.(4F).6p b 5F* → 5d8.(3F<4>).6s.6d b (4,?)	Measured	NIST
420.12097 nm	470	Pt I	emission	5d9.6p 3P* → 5d9.7s 3D	Measured	NIST

Extended Properties

Covalent Radii (Extended)

Covalent radius (Pyykkö)

Covalent radius (Pyykkö, double)

Covalent radius (Pyykkö, triple)

Van der Waals Radii

Batsanov

Alvarez

UFF

MM3

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 (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

Melting point	2041.35 K
Boiling point	4098.15 K

Oxidation State Categories

−3 extended

+6 extended

+1 extended

−2 extended

−1 extended

+3 extended

+5 extended

+2 main

+4 main

0 extended

Advanced Reference Data

Screening Constants (14)

n	Orbital	σ
1	s	1.506
2	p	4.4746
2	s	20.3702
3	d	13.5027
3	p	22.1139
3	s	23.0157
4	d	37.37
4	f	38.494
4	p	35.2696
4	s	34.3612

Crystal Radii Detail (4)

Charge	CN	r_crystal (pm)	Origin
2	IVSQ	74
2	VI	94	Ahrens (1952) ionic radius,
4	VI	76.5	from r^3 vs V plots,
5	VI	71	estimated, from r^3 vs V plots,

Isotope Decay Modes (67)

Isotope	Mode	Intensity
165	A	100%
166	A	100%
167	A	100%
168	A	100%
168	B+	—
169	A	100%
169	B+	—
170	A	100%
170	B+	—
171	A	86%

X‑ray Scattering Factors (945)

Energy (eV)	f₁	f₂
0.1	-0.0027	0.00979
0.13	-0.0033	0.01359
0.15	-0.0035	0.01538
0.17	-0.0037	0.01722
0.2	-0.0043	0.02103
0.22	-0.0045	0.02279
0.25	-0.0051	0.02656
0.28	-0.0056	0.0304
0.3	-0.0058	0.03194
0.32	-0.0058	0.03342

Additional Data

Estimated Crustal Abundance

The estimated element abundance in the earth's crust.

5×10-3 milligrams per kilogram

References (1)

[5] Platinum https://education.jlab.org/itselemental/ele078.html

Estimated Oceanic Abundance

The estimated element abundance in the earth's oceans.

Not Applicable

References (1)

[5] Platinum https://education.jlab.org/itselemental/ele078.html

Sources

Sources of this element.

Platinum occurs natively, accompanied by small quantities of iridium, osmium, palladium, ruthenium, and rhodium, all belonging to the same group of metals. These are found in the alluvial deposits of the Ural mountains, of Columbia, and of certain western American states. Sperrylite, occurring with the nickel-bearing deposits of Sudbury, Ontario, is the source of a considerable amount of metal.

The large production of nickel makes up for the fact that is only one part of the platinum metals in two million parts of ore.

References (1)

[6] Platinum https://periodic.lanl.gov/78.shtml

References

(9)

1 PubChem

Data deposited in or computed by PubChem

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

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

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

Platinum

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.

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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.

Visit source License

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

Platinum

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/

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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

Platinum

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.

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7 NIST Physical Measurement Laboratory

Platinum

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

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8 PubChem Elements

Platinum

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

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9 PubChem Elements

Platinum

The element property data was retrieved from publications.

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Last updated: May 1, 2026

Data verified: May 12, 2026

Content is reviewed against latest scientific data.