Palladium (Pd)
transition-metalSolid
Standard Atomic Weight
106.42 uElectron configuration
[Kr] 4d10Melting point
1554.9 °CBoiling point
2962.85 °CDensity
1.2e+4 kg/m³Oxidation states
+1, +2, +3, +4, +5Electronegativity (Pauling)
2.2Ionization energy (1st)
8.336839 eVDiscovery year
1803Atomic radius
140 pmDetails
Palladium is a silvery platinum-group metal with high catalytic activity and an unusual ability to absorb large amounts of hydrogen into its lattice. It is chemically noble in air at ordinary temperatures, but it forms many complexes and is readily used in surface chemistry. Its technological importance is dominated by vehicle emission control, fine-chemical catalysis, electronics, and hydrogen-related applications.
The element is a silvery-white metal, it does not tarnish in air, and it is the least dense and lowest melting of the platinum group of metals. When annealed, it is soft and ductile; cold-working greatly increases its strength and hardness. Palladium is attacked by nitric and sulfuric acid.
At room temperatures, the metal has the unusual property of absorbing up to 900 times its own volume of hydrogen, possibly forming Pd2H. It is not yet clear if this is a true compound. Hydrogen readily diffuses through heated palladium, providing a means of purifying the gas.
The name derives from the second largest asteroid of the solar system Pallas (named after the goddess of wisdom and arts—Pallas Athene). The element was discovered by the English chemist and physicist William Hyde Wollaston in 1803, one year after the discovery of Pallas by the German astronomer Wilhelm Olbers in 1802. The discovery was originally published anonymously by Wollaston to obtain priority, while not disclosing any details about his preparation.
Palladium was discovered by William Hyde Wollaston, an English chemist, in 1803 while analyzing samples of platinum ore that were obtained from South America. Although it is a rare element, palladium tends to occur along with deposits of platinum, nickel, copper, silver and gold and is recovered as a byproduct of mining these other metals.
Palladium was named after the asteroid Pallas, which was discovered at about the same time. Pallas was the Greek goddess of wisdom.
Pure palladium is a lustrous, silver-white metal. It is soft and ductile when annealed, can be rolled into thin foil, and does not tarnish rapidly in clean air. Finely divided palladium is gray to black and has much higher surface reactivity than the compact metal.
The largest use of palladium is in catalytic converters, especially for oxidation of carbon monoxide and hydrocarbons and reduction reactions in exhaust systems. Palladium catalysts are also central to hydrogenation and carbon–carbon coupling reactions in chemical manufacture. The metal is used in multilayer ceramic capacitors, electrical contacts, dental alloys, some jewelry alloys, hydrogen purification membranes, and laboratory catalysts such as palladium on carbon.
Palladium is used to make springs for watches, surgical instruments, electrical contacts and dental fillings and crowns. Finely divided palladium acts as a catalyst and is used in hydrogenation and dehydrogenation processes. Palladium at room temperature can absorb up to 900 times its own volume of hydrogen. Hydrogen will easily pass through heated palladium, a property that allows for the easy purification of hydrogen. Palladium alloys are used to make jewelry and, when alloyed with gold, forms a material known as white gold.
Palladium dichloride (PdCl2), a palladium compound, can absorb large amounts of carbon monoxide (CO) gas and is used in carbon monoxide detectors.
Finely divided palladium is a good catalyst and is used for hydrogenation and dehydrogenation reactions. It is alloyed and used in jewelry trades.
White gold is an alloy of gold decolorized by the addition of palladium. Like gold, palladium can be beaten into leaf as thin as 1/250,000 in. The metal is used in dentistry, watch making, and in making surgical instruments and electrical contacts.
Isotopes in Earth/Planetary Science
Small palladium nucleosynthetic anomalies in isotopic composition (related to s-process variability) were identified in type IVB iron meteorites [340] B. Mayer, N. Wittig, M. Humayun, I. Leya. Astrophys. J.809, 180 (2015).. These nucleosynthetic isotope anomalies may represent spatial and/or temporal heterogeneity in the early solar nebula or may be due to chemical processing within the solar nebula [327] N. Dauphas, A. M. Davis, B. Marty, L. Reisberg. Earth Planet. Sci. Lett.226, 465 (2004)., [341] A. Trinquier, T. Elliott, D. Ulfbeck, C. Coath, A. N. Krot, M. Bizzarro. Science324, 374 (2009).. Palladium and molybdenum isotopic compositions on selected iron meteorites are correlated (Fig. IUPAC.46.1). One possible conclusion is that “a common presolar carrier must have been thermally processed on which the more volatile (a measure of the tendency of a substance to vaporize) Pd was lost and homogenized in the solar nebula, resulting in the deviation from the s-process” variability [342] B. Mayer, K. R. Bermingham, E. A. Worsham, M. Humayun, R. J. Walker. “Correlated nucleosynthetic anomalies in Mo, Ru, and Pd from iron meteorites”, in 47th Lunar and Planetary Science Conference.. Because these palladium (and other element) anomalies are persistent throughout the measured iron meteorites, the thermal processing must have occurred prior to the formation of the parent body that produced iron meteorites [342] B. Mayer, K. R. Bermingham, E. A. Worsham, M. Humayun, R. J. Walker. “Correlated nucleosynthetic anomalies in Mo, Ru, and Pd from iron meteorites”, in 47th Lunar and Planetary Science Conference..
Isotopes in Geochronology
The isotope-amount ratio n(107Pd)/n(107Ag) is used in geochronology to help date major thermal events in the Solar System. Although 107Ag is naturally occurring, 107Ag is also the daughter product of the beta decay of 107Pd. If both excess 107Ag and 107Pd (with a half-life of 6.5×106 years) are present in a sample of extraterrestrial origin, then the material would have formed sometime after 107Pd decayed. The n(107Pd)/n(107Ag) amount ratio can be measured to help determine when the 107Pd decay process began and how much time has elapsed since the material was formed [344] W. R. Kelly, G. J. Wasserburg. Geophys. Res. Lett.5 1079 (1978)., [345] G. J. Wasserburg, D. A. Papanastassiou. Some Short-Lived Nuclides in the Early Solar-System – A Connection with the Placental ISM, in Essays in Nuclear Astrophysics, C. A. Barnes, D. D. Clayton, and D. N. Schramm. Cambridge University Press, Cambridge, UK (1982)., [346] J. H. Chen, G. J. Wasserburg. Live 107Pd in the Early Solar System and Implications on Planetary Evolution, in Earth Processes: Reading the Isotopic Code, Geophysical Monograph 95, A. Basu and S. Hart. Amer. Geophys. U., Washington (1996)., [347] J. H. Chen, G. J. Wasserburg. Geochim. Cosmochim. Acta54, 1729 (1990)., [348] A. P. Dicken. Radiogenic Isotope Geology, Cambridge University Press, New York (1995)..
Isotopes in Medicine
Seeds of the radioactive isotope 103Pd are internally placed in the body to fight prostate and other cancers locally. 103Pd has a half-life of 16.99 days and releases energy at about 80 X-rays and 186 Auger electrons per 100 decays of 103Pd. Therefore, this makes this isotope an ideal candidate for internal radiotherapy for the treatment of cancers [349] M. Hussain, S. Sudar, M. N. Aslam, H. A. Shah, R. Ahmad, A. A. Malik, S. M. Qaim. Appl. Radiat. Isot.67, 1842 (2009)..
The radioisotope 109Pd (with a half-life of 13.5 h) can be used as a form of cancer therapy. For example, 109Pd-labeled porphyrins or porphyrin-like substances are used as diagnostic and therapeutic techniques to help locate and address areas of tumorous growth. Porphyrins accumulate in tumors of the body and when radiolabeled porphyrins are introduced to the body, the X-rays and energy released can help determine the location and even treat the cancerous tumors [350] T. Das, S. Chakraborty, H. D. Sarma, S. Banerjee. Radiochim. Acta96, 427 (2008)..
Isotopes Used as a Source of Radioactive Isotope(s)
104Pd is the major target used for cyclotron production of the medically important radioactive isotope 103Pd via the reaction 104Pd (p, p n) 103Pd [349] M. Hussain, S. Sudar, M. N. Aslam, H. A. Shah, R. Ahmad, A. A. Malik, S. M. Qaim. Appl. Radiat. Isot.67, 1842 (2009)..
Palladium most often shows oxidation states +2 and 0, with +4 important in some fluorides and complex salts. Palladium(II) chloride, PdCl₂, is a common starting material for coordination compounds and catalysts. Tetrakis(triphenylphosphine)palladium(0), Pd[P(C₆H₅)₃]₄, is a widely used homogeneous catalyst precursor. Palladium(II) acetate, Pd(CH₃COO)₂, and palladium on carbon are frequent sources of active palladium species in organic synthesis.
See more information at the Palladium compound page.
Compact palladium metal is not highly reactive and presents low acute toxicity, but dusts and finely divided catalysts can be irritating and may ignite adsorbed hydrogen or organic material under unfavorable conditions. Soluble palladium salts and organopalladium compounds can cause skin sensitization and other toxic effects. Spent catalysts may contain hazardous residues from the processes in which they were used.
Palladium occurs naturally at low concentrations, mainly with other platinum-group elements in sulfide and chromite-associated ores. Environmental releases are increased by abrasion and loss from automotive catalysts, creating fine particles in road dust and nearby soils. Palladium is generally sparingly soluble in many natural waters, but complexing ligands such as chloride and organic matter can increase mobility.
Palladium is obtained chiefly as a by-product of nickel, copper, and platinum-group metal mining and refining, so supply cannot respond as independently as demand for a primary metal. Major demand comes from emission-control catalysts, with electronics, chemical catalysts, dentistry, and jewelry making smaller contributions. Recycling from spent automotive catalysts is an important secondary source. Substitution with platinum or rhodium is possible in some catalyst systems but depends on performance, regulation, and relative availability.
Discovered in 1803 by Wollaston, Palladium is found with platinum and other metals of the platinum group in placer deposits of Russia, South America, North America, Ethiopia, and Australia. It is also found associated with the nickel-copper deposits of South Africa and Ontario. Palladium's separation from the platinum metals depends upon the type of ore in which it is found.
Palladium is a heavy element produced mainly by neutron-capture processes in earlier generations of stars. It is much less abundant cosmically than iron or nickel but is present in meteorites and planetary materials with other siderophile and chalcophile elements. On Earth it was partly concentrated into the core during differentiation, leaving crustal concentrations low.
- Palladium can absorb hydrogen to form non-stoichiometric palladium hydride without becoming a simple fixed-ratio salt.
- The element was named after the asteroid Pallas, which had been discovered shortly before palladium.
- Palladium-gold alloys are used to make white gold in some jewelry.
- Carbon monoxide binds strongly to palladium surfaces, a key feature of exhaust catalysis.
- Palladium leaf can be made, but it is less familiar than gold leaf because the metal is far rarer and costlier.
Images
Properties
Physical
- Atomic radius (empirical)
- 140 pm Compare Atomic radius (empirical) of all elements →
- Covalent radius
- 139 pm Compare Covalent radius of all elements →
- Van der Waals radius
- 202 pm Compare Van der Waals radius of all elements →
- Metallic radius
- 128 pm Compare Metallic radius of all elements →
- Density
- 1.2 × 104 kg/m³ Compare Density of all elements →
- Molar volume
- 0.0089 L/mol
- Phase at STP
- Solid Compare Phase at STP of all elements →
- Melting point
- 1554.9 °C Compare Melting point of all elements →
- Boiling point
- 2962.85 °C Compare Boiling point of all elements →
- Thermal conductivity
- 71.8 W/(m·K) Compare Thermal conductivity of all elements →
- Specific heat capacity
- 0.246 J/(g·K) Compare Specific heat capacity of all elements →
- Molar heat capacity
- 25.98 J/(mol·K) Compare Molar heat capacity of all elements →
- Crystal structure
- Face-centered cubic Compare Crystal structure of all elements →
Chemical
- Electronegativity (Pauling)
- 2.2 Compare Electronegativity (Pauling) of all elements →
- Electronegativity (Allen)
- 1.58
- Electron affinity
- 0.557 eV
- Ionization energy (1st)
- 8.336839 eV Compare Ionization energy (1st) of all elements →
- Ionization energy (2nd)
- 19.430067 eV Compare Ionization energy (2nd) of all elements →
- Ionization energy (3rd)
- 32.930113 eV Compare Ionization energy (3rd) of all elements →
- Ionization energy (4th)
- 46.000158 eV Compare Ionization energy (4th) of all elements →
- Ionization energy (5th)
- 61.00021 eV Compare Ionization energy (5th) of all elements →
- Oxidation states
- +1, +2, +3, +4, +5 Compare Oxidation states of all elements →
- Valence electrons
- 10 Compare Valence electrons of all elements →
- Electron configuration
- [Kr] 4d10
Thermodynamic
- Heat of fusion
- 0.17349847 eV Compare Heat of fusion of all elements →
- Heat of vaporization
- 3.700057 eV Compare Heat of vaporization of all elements →
- Heat of sublimation
- 3.907343 eV
- Heat of atomization
- 3.907343 eV
- Atomization enthalpy
- 3.903197 eV
Nuclear
- Protons
- 46 Compare Protons of all elements →
- Neutrons
- 60 Compare Neutrons of all elements →
- Known isotopes
- 42 Compare Known isotopes of all elements →
- Stable isotopes
- 4 Compare Stable isotopes of all elements →
- Most stable isotope
- Pd-106
- Discovery year
- 1803
Abundance
- Abundance (Earth's crust)
- 0.015 mg/kg Compare Abundance (Earth's crust) of all elements →
Crystal Structure
- Lattice constant a
- 389 pm
Electronic Structure
- Electrons per shell
- 2, 8, 18, 18 Compare Electrons per shell of all elements →
Identifiers
- CAS number
- 7440-05-3 Compare CAS number of all elements →
- Term symbol
- 1S0
- InChI
- InChI=1S/Pd
- InChI Key
- KDLHZDBZIXYQEI-UHFFFAOYSA-N
Electron Configuration Measured
Pd: 4d¹⁰[Kr] 4d¹⁰1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰Atomic model
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
Isotope Distribution
| Mass number | Atomic mass (u) | Natural abundance | Half-life |
|---|---|---|---|
| 104 Stable | 103.9040305 ± 0.0000014 | 11.1400% | Stable |
| 105 Stable | 104.9050796 ± 0.0000012 | 22.3300% | Stable |
| 106 Stable | 105.9034804 ± 0.0000012 | 27.3300% | Stable |
| 108 Stable | 107.9038916 ± 0.0000012 | 26.4600% | Stable |
Phase / State
Reason: 1529.9 °C below melting point (1554.9 °C)
Schematic, not to scale
Phase transition points
Transition energies
Energy required to melt 1 mol at melting point
Energy required to vaporize 1 mol at boiling point
Energy required to sublime 1 mol at sublimation point
Density
At standard conditions
At standard conditions
Atomic Spectra
Showing 10 of 46. Sorted by ion charge (ascending).
Lines Holdings ?
| Ion | Charge | Total lines | Transition probabilities | Level designations |
|---|---|---|---|---|
| Pd I | 0 | 76 | 8 | 75 |
| Pd II | +1 | 62 | 10 | 62 |
| Pd III | +2 | 75 | 0 | 0 |
Levels Holdings ?
| Ion | Charge | Levels |
|---|---|---|
| Pd I | 0 | 145 |
| Pd II | +1 | 186 |
| Pd III | +2 | 177 |
| Pd IV | +3 | 2 |
| Pd V | +4 | 2 |
| Pd VI | +5 | 2 |
| Pd VII | +6 | 2 |
| Pd VIII | +7 | 2 |
| Pd IX | +8 | 2 |
| Pd X | +9 | 2 |
Ionic Radii
| Charge | Coordination | Spin | Radius |
|---|---|---|---|
| +1 | 2 | N/A | 59 pm |
| +2 | 4 | N/A | 64 pm |
| +2 | 6 | N/A | 86 pm |
| +3 | 6 | N/A | 76 pm |
| +4 | 6 | N/A | 61.5 pm |
Compounds
Isotopes (4)
| Mass number | Atomic mass (u) | Natural abundance | Half-life | Decay mode | |
|---|---|---|---|---|---|
| 104 Stable | 103.9040305 ± 0.0000014 | 11.1400% ± 0.0800% | Stable | stable | |
| 105 Stable | 104.9050796 ± 0.0000012 | 22.3300% ± 0.0800% | Stable | stable | |
| 106 Stable | 105.9034804 ± 0.0000012 | 27.3300% ± 0.0300% | Stable | stable | |
| 108 Stable | 107.9038916 ± 0.0000012 | 26.4600% ± 0.0900% | Stable | stable |
Spectral Lines
| Wavelength (nm) | Intensity | Ion stage | Type | Transition | Accuracy | Source | |
|---|---|---|---|---|---|---|---|
| 383.2286 nm | 1500 | Pd I | emission | 4d9.(2D<3/2>).5s 2[3/2] → 4d9.(2D<5/2>).5p 2[3/2]* | Measured | NIST | |
| 389.41982 nm | 2200 | Pd I | emission | 4d9.(2D<3/2>).5s 2[3/2] → 4d9.(2D<5/2>).5p 2[5/2]* | Measured | NIST | |
| 395.86229 nm | 1500 | Pd I | emission | 4d9.(2D<3/2>).5s 2[3/2] → 4d9.(2D<5/2>).5p 2[5/2]* | Measured | NIST | |
| 408.73428 nm | 290 | Pd I | emission | 4d9.(2D<3/2>).5s 2[3/2] → 4d9.(2D<5/2>).5p 2[3/2]* | Measured | NIST | |
| 416.98387 nm | 90 | Pd I | emission | 4d9.(2D<3/2>).5s 2[3/2] → 4d9.(2D<5/2>).5p 2[3/2]* | Measured | NIST | |
| 421.29533 nm | 2500 | Pd I | emission | 4d9.(2D<3/2>).5s 2[3/2] → 4d9.(2D<5/2>).5p 2[7/2]* | Measured | NIST | |
| 447.35846 nm | 180 | Pd I | emission | 4d9.(2D<3/2>).5s 2[3/2] → 4d9.(2D<5/2>).5p 2[3/2]* | Measured | NIST | |
| 478.81874 nm | N/A | Pd I | emission | 4d9.(2D<5/2>).5p 2[3/2]* → 4d9.(2D<5/2>).5d 2[5/2] | Measured | NIST | |
| 481.75067 nm | N/A | Pd I | emission | 4d9.(2D<5/2>).5p 2[3/2]* → 4d9.(2D<5/2>).5d 2[3/2] | Measured | NIST | |
| 487.54251 nm | 35 | Pd I | emission | 4d9.(2D<5/2>).5p 2[3/2]* → 4d9.(2D<5/2>).5d 2[1/2] | Measured | NIST | |
| 511.08092 nm | 55 | Pd I | emission | 4d9.(2D<5/2>).5p 2[7/2]* → 4d9.(2D<5/2>).5d 2[7/2] | Measured | NIST | |
| 511.70072 nm | 75 | Pd I | emission | 4d9.(2D<3/2>).5p 2[5/2]* → 4d9.(2D<3/2>).5d 2[7/2] | Measured | NIST | |
| 516.38405 nm | 160 | Pd I | emission | 4d9.(2D<5/2>).5p 2[7/2]* → 4d9.(2D<5/2>).5d 2[9/2] | Measured | NIST | |
| 523.48612 nm | 55 | Pd I | emission | 4d9.(2D<5/2>).5p 2[7/2]* → 4d9.(2D<5/2>).5d 2[7/2] | Measured | NIST | |
| 529.56266 nm | 120 | Pd I | emission | 4d9.(2D<5/2>).5p 2[7/2]* → 4d9.(2D<5/2>).5d 2[9/2] | Measured | NIST | |
| 531.25867 nm | 18 | Pd I | emission | 4d9.(2D<5/2>).5p 2[3/2]* → 4d9.(2D<5/2>).5d 2[5/2] | Measured | NIST | |
| 534.51048 nm | 15 | Pd I | emission | 4d9.(2D<3/2>).5p 2[5/2]* → 4d9.(2D<3/2>).5d 2[5/2] | Measured | NIST | |
| 539.52204 nm | 35 | Pd I | emission | 4d9.(2D<3/2>).5p 2[5/2]* → 4d9.(2D<3/2>).5d 2[7/2] | Measured | NIST | |
| 554.28067 nm | 55 | Pd I | emission | 4d9.(2D<5/2>).5p 2[5/2]* → 4d9.(2D<5/2>).5d 2[7/2] | Measured | NIST | |
| 554.70204 nm | 35 | Pd I | emission | 4d9.(2D<5/2>).5p 2[5/2]* → 4d9.(2D<5/2>).5d 2[5/2] | Measured | NIST | |
| 561.94631 nm | 27 | Pd I | emission | 4d9.(2D<3/2>).5p 2[3/2]* → 4d9.(2D<3/2>).5d 2[5/2] | Measured | NIST | |
| 564.27039 nm | 15 | Pd I | emission | 4d9.(2D<3/2>).5p 2[1/2]* → 4d9.(2D<3/2>).5d 2[3/2] | Measured | NIST | |
| 565.54366 nm | 14 | Pd I | emission | 4d9.(2D<3/2>).5p 2[3/2]* → 4d9.(2D<3/2>).5d 2[5/2] | Measured | NIST | |
| 567.00702 nm | 75 | Pd I | emission | 4d9.(2D<5/2>).5p 2[5/2]* → 4d9.(2D<5/2>).5d 2[7/2] | Measured | NIST | |
| 569.0128 nm | 11 | Pd I | emission | 4d9.(2D<3/2>).5p 2[1/2]* → 4d9.(2D<3/2>).5d 2[3/2] | Measured | NIST | |
| 569.50921 nm | N/A | Pd I | emission | 4d9.(2D<5/2>).5p 2[5/2]* → 4d9.(2D<5/2>).5d 2[5/2] | Measured | NIST | |
| 573.66175 nm | 18 | Pd I | emission | 4d9.(2D<5/2>).5p 2[5/2]* → 4d9.(2D<5/2>).5d 2[3/2] | Measured | NIST | |
| 677.45174 nm | 23 | Pd I | emission | 4d8.5s2 3F → 4d9.(2D<3/2>).5p 2[5/2]* | Measured | NIST | |
| 678.44893 nm | 65 | Pd I | emission | 4d9.(2D<5/2>).5p 2[3/2]* → 4d9.(2D<5/2>).6s 2[5/2] | Measured | NIST | |
| 683.3446 nm | N/A | Pd I | emission | 4d9.(2D<3/2>).5p 2[3/2]* → 4d9.(2D<5/2>).5d 2[5/2] | Measured | NIST | |
| 701.6446 nm | 11 | Pd I | emission | 4d9.(2D<3/2>).5p 2[1/2]* → 4d9.(2D<3/2>).6s 2[3/2] | Measured | NIST | |
| 731.0053 nm | N/A | Pd I | emission | 4d9.(2D<3/2>).5p 2[5/2]* → 4d9.(2D<3/2>).6s 2[3/2] | Measured | NIST | |
| 736.8096 nm | 75 | Pd I | emission | 4d9.(2D<5/2>).5p 2[7/2]* → 4d9.(2D<5/2>).6s 2[5/2] | Measured | NIST | |
| 739.19 nm | 27 | Pd I | emission | 4d9.(2D<3/2>).5p 2[5/2]* → 4d9.(2D<3/2>).6s 2[3/2] | Measured | NIST | |
| 748.6909 nm | 16 | Pd I | emission | 4d9.(2D<5/2>).5p 2[7/2]* → 4d9.(2D<5/2>).6s 2[5/2] | Measured | NIST |
Extended Properties
Covalent Radii (Extended)
- Covalent radius (Pyykkö)
- 120 pm
- Covalent radius (Pyykkö, double)
- 117 pm
- Covalent radius (Pyykkö, triple)
- 112 pm
Van der Waals Radii
- Batsanov
- 205 pm
- Alvarez
- 215 pm
- UFF
- 289.9 pm
- MM3
- 237 pm
Atomic & Metallic Radii
- Atomic radius (Rahm)
- 215 pm
- Metallic radius (C12)
- 137 pm
Numbering Scales
- Mendeleev
- 68
- Pettifor
- 69
- Glawe
- 65
Electronegativity Scales
- Ghosh
- 0
- Miedema
- 5
- Gunnarsson–Lundqvist
- 3
- Robles–Bartolotti
- 2
Polarizability & Dispersion
- Dipole polarizability
- 26.14 a.u.
- Dipole polarizability (unc.)
- 0.1 a.u.
- C₆ (Gould–Bučko)
- 628 Ha·Bohr6
Chemical Affinity
- Proton affinity
- 696 kJ/mol
- Gas basicity
- 673.4 kJ/mol
Miedema Parameters
- Miedema molar volume
- 8.9 cm3/mol
- Miedema electron density
- 5
Supply Risk & Economics
- Production concentration
- 60
- Relative supply risk
- 8
- Reserve distribution
- 95
- Political stability (top producer)
- 44
- Political stability (top reserve)
- 44
Phase Transitions & Allotropes
| Melting point | 1827.95 K |
| Boiling point | 3236.15 K |
Oxidation State Categories
Advanced Reference Data
Screening Constants (9)
| n | Orbital | σ |
|---|---|---|
| 1 | s | 0.9411 |
| 2 | p | 4.07 |
| 2 | s | 12.1172 |
| 3 | d | 14.5489 |
| 3 | p | 16.9804 |
| 3 | s | 16.7788 |
| 4 | d | 32.3824 |
| 4 | p | 28.2768 |
| 4 | s | 27.014 |
Crystal Radii Detail (5)
| Charge | CN | Spin | rcrystal (pm) | Origin |
|---|---|---|---|---|
| 1 | II | 73 | ||
| 2 | IVSQ | 78 | ||
| 2 | VI | 100 | ||
| 3 | VI | 90 | ||
| 4 | VI | 75.5 | from r^3 vs V plots, |
Isotope Decay Modes (62)
| Isotope | Mode | Intensity |
|---|---|---|
| 90 | B+ | — |
| 90 | B+p | — |
| 90 | 2p | — |
| 91 | B+ | 100% |
| 91 | B+p | 3.1% |
| 92 | B+ | 100% |
| 92 | B+p | 1.6% |
| 93 | B+ | 100% |
| 93 | B+p | 7.4% |
| 94 | B+ | 100% |
X‑ray Scattering Factors (507)
| Energy (eV) | f₁ | f₂ |
|---|---|---|
| 10 | — | 1.15058 |
| 10.1617 | — | 1.2095 |
| 10.3261 | — | 1.27144 |
| 10.4931 | — | 1.33655 |
| 10.6628 | — | 1.40499 |
| 10.8353 | — | 1.47694 |
| 11.0106 | — | 1.54695 |
| 11.1886 | — | 1.61473 |
| 11.3696 | — | 1.68548 |
| 11.5535 | — | 1.75934 |
Additional Data
Estimated Crustal Abundance
The estimated element abundance in the earth's crust.
1.5×10-2 milligrams per kilogram
References (1)
- [5] Palladium https://education.jlab.org/itselemental/ele046.html
Estimated Oceanic Abundance
The estimated element abundance in the earth's oceans.
Not Applicable
References (1)
- [5] Palladium https://education.jlab.org/itselemental/ele046.html
Sources
Sources of this element.
Discovered in 1803 by Wollaston, Palladium is found with platinum and other metals of the platinum group in placer deposits of Russia, South America, North America, Ethiopia, and Australia. It is also found associated with the nickel-copper deposits of South Africa and Ontario. Palladium's separation from the platinum metals depends upon the type of ore in which it is found.
References (1)
- [6] Palladium https://periodic.lanl.gov/46.shtml
References
(9)
Data deposited in or computed by PubChem
The half-life and atomic mass data was provided by the Atomic Mass Data Center at the International Atomic Energy Agency.
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.
The information are cited from Pure Appl. Chem. 2018; 90(12): 1833-2092, https://doi.org/10.1515/pac-2015-0703.
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/
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.
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
This section provides all form of data related to element Palladium.
The element property data was retrieved from publications.