Palladium (Pd)
transition-metalSolid
Peso atomico standard
106,42 uConfigurazione elettronica
[Kr] 4d10Punto di fusione
1554,9 °CPunto di ebollizione
2962,85 °CDensità
1,2e+4 kg/m³Stati di ossidazione
+1, +2, +3, +4, +5Elettronegatività (Pauling)
2,2Energia di ionizzazione (1ª)
8,336839 eVAnno della scoperta
1803Raggio atomico
140 pmDettagli
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.
Immagini
Proprietà
Fisiche
- Raggio atomico (empirico)
- 140 pm Confronta Raggio atomico (empirico) di tutti gli elementi →
- Raggio covalente
- 139 pm Confronta Raggio covalente di tutti gli elementi →
- Raggio di van der Waals
- 202 pm Confronta Raggio di van der Waals di tutti gli elementi →
- Raggio metallico
- 128 pm Confronta Raggio metallico di tutti gli elementi →
- Densità
- 1,2 × 104 kg/m³ Confronta Densità di tutti gli elementi →
- Volume molare
- 0,0089 L/mol
- Fase in condizioni STP
- Solido Confronta Fase in condizioni STP di tutti gli elementi →
- Punto di fusione
- 1554,9 °C Confronta Punto di fusione di tutti gli elementi →
- Punto di ebollizione
- 2962,85 °C Confronta Punto di ebollizione di tutti gli elementi →
- Conducibilità termica
- 71,8 W/(m·K) Confronta Conducibilità termica di tutti gli elementi →
- Capacità termica specifica
- 0,246 J/(g·K) Confronta Capacità termica specifica di tutti gli elementi →
- Capacità termica molare
- 25,98 J/(mol·K) Confronta Capacità termica molare di tutti gli elementi →
- Struttura cristallina
- Cubica a facce centrate Confronta Struttura cristallina di tutti gli elementi →
Chimiche
- Elettronegatività (Pauling)
- 2,2 Confronta Elettronegatività (Pauling) di tutti gli elementi →
- Elettronegatività (Allen)
- 1,58
- Affinità elettronica
- 0,557 eV
- Energia di ionizzazione (1ª)
- 8,336839 eV Confronta Energia di ionizzazione (1ª) di tutti gli elementi →
- Energia di ionizzazione (2ª)
- 19,430067 eV Confronta Energia di ionizzazione (2ª) di tutti gli elementi →
- Energia di ionizzazione (3ª)
- 32,930113 eV Confronta Energia di ionizzazione (3ª) di tutti gli elementi →
- Energia di ionizzazione (4ª)
- 46,000158 eV Confronta Energia di ionizzazione (4ª) di tutti gli elementi →
- Energia di ionizzazione (5ª)
- 61,00021 eV Confronta Energia di ionizzazione (5ª) di tutti gli elementi →
- Stati di ossidazione
- +1, +2, +3, +4, +5 Confronta Stati di ossidazione di tutti gli elementi →
- Elettroni di valenza
- 10 Confronta Elettroni di valenza di tutti gli elementi →
- Configurazione elettronica
- [Kr] 4d10
Termodinamiche
- Calore di fusione
- 0,17349847 eV Confronta Calore di fusione di tutti gli elementi →
- Calore di vaporizzazione
- 3,700057 eV Confronta Calore di vaporizzazione di tutti gli elementi →
- Calore di sublimazione
- 3,907343 eV
- Calore di atomizzazione
- 3,907343 eV
- Entalpia di atomizzazione
- 3,903197 eV
Nucleari
- Protoni
- 46 Confronta Protoni di tutti gli elementi →
- Neutroni
- 60 Confronta Neutroni di tutti gli elementi →
- Isotopi noti
- 42 Confronta Isotopi noti di tutti gli elementi →
- Isotopi stabili
- 4 Confronta Isotopi stabili di tutti gli elementi →
- Isotopo più stabile
- Pd-106
- Anno della scoperta
- 1803
Abbondanza
- Abbondanza (crosta terrestre)
- 0,015 mg/kg Confronta Abbondanza (crosta terrestre) di tutti gli elementi →
Struttura cristallina
- Costante reticolare a
- 389 pm
Struttura elettronica
- Elettroni per guscio
- 2, 8, 18, 18 Confronta Elettroni per guscio di tutti gli elementi →
Identificativi
- Numero CAS
- 7440-05-3 Confronta Numero CAS di tutti gli elementi →
- Simbolo di termine
- 1S0
- InChI
- InChI=1S/Pd
- Chiave InChI
- KDLHZDBZIXYQEI-UHFFFAOYSA-N
Configurazione elettronica Misurato
Pd: 4d¹⁰[Kr] 4d¹⁰1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰Modello atomico
Gli isotopi modificano il numero di neutroni, la massa e la stabilità — non la configurazione elettronica di un atomo neutro.
Modello atomico schematico, non in scala.
Impronta atomica
Spettro di emissione / assorbimento
Distribuzione isotopica
| Numero di massa | Massa atomica (u) | Abbondanza naturale | Emivita |
|---|---|---|---|
| 104 Stabile | 103,9040305 ± 0,0000014 | 11,1400% | Stabile |
| 105 Stabile | 104,9050796 ± 0,0000012 | 22,3300% | Stabile |
| 106 Stabile | 105,9034804 ± 0,0000012 | 27,3300% | Stabile |
| 108 Stabile | 107,9038916 ± 0,0000012 | 26,4600% | Stabile |
Fase / Stato
Motivo: 1529,9 °C sotto il punto di fusione (1554,9 °C)
Schema non in scala
Punti di transizione di fase
Energie di transizione
Energia necessaria per fondere 1 mol al punto di fusione
Energia necessaria per vaporizzare 1 mol al punto di ebollizione
Energia necessaria per sublimare 1 mol al punto di sublimazione
Densità
In condizioni standard
In condizioni standard
Spettri atomici
Sono visualizzati 10 di 46. Ordinamento per carica ionica crescente.
Righe disponibili ?
| Ione | Carica | Righe totali | Probabilità di transizione | Designazioni dei livelli |
|---|---|---|---|---|
| Pd I | 0 | 76 | 8 | 75 |
| Pd II | +1 | 62 | 10 | 62 |
| Pd III | +2 | 75 | 0 | 0 |
Livelli disponibili ?
| Ione | Carica | Livelli |
|---|---|---|
| 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 |
Raggi ionici
| Carica | Coordinazione | Spin | Raggio |
|---|---|---|---|
| +1 | 2 | N/D | 59 pm |
| +2 | 4 | N/D | 64 pm |
| +2 | 6 | N/D | 86 pm |
| +3 | 6 | N/D | 76 pm |
| +4 | 6 | N/D | 61.5 pm |
Composti
Isotopi (4)
| Numero di massa | Massa atomica (u) | Abbondanza naturale | Emivita | Modalità di decadimento | |
|---|---|---|---|---|---|
| 104 Stabile | 103,9040305 ± 0,0000014 | 11,1400% ± 0,0800% | Stabile | stable | |
| 105 Stabile | 104,9050796 ± 0,0000012 | 22,3300% ± 0,0800% | Stabile | stable | |
| 106 Stabile | 105,9034804 ± 0,0000012 | 27,3300% ± 0,0300% | Stabile | stable | |
| 108 Stabile | 107,9038916 ± 0,0000012 | 26,4600% ± 0,0900% | Stabile | stable |
Righe spettrali
| Lunghezza d'onda (nm) | Intensità | Stadio di ionizzazione | Tipo | Transizione | Accuratezza | Fonte | |
|---|---|---|---|---|---|---|---|
| 383.2286 nm | 1500 | Pd I | emission | 4d9.(2D<3/2>).5s 2[3/2] → 4d9.(2D<5/2>).5p 2[3/2]* | Misurata | NIST | |
| 389.41982 nm | 2200 | Pd I | emission | 4d9.(2D<3/2>).5s 2[3/2] → 4d9.(2D<5/2>).5p 2[5/2]* | Misurata | NIST | |
| 395.86229 nm | 1500 | Pd I | emission | 4d9.(2D<3/2>).5s 2[3/2] → 4d9.(2D<5/2>).5p 2[5/2]* | Misurata | NIST | |
| 408.73428 nm | 290 | Pd I | emission | 4d9.(2D<3/2>).5s 2[3/2] → 4d9.(2D<5/2>).5p 2[3/2]* | Misurata | NIST | |
| 416.98387 nm | 90 | Pd I | emission | 4d9.(2D<3/2>).5s 2[3/2] → 4d9.(2D<5/2>).5p 2[3/2]* | Misurata | NIST | |
| 421.29533 nm | 2500 | Pd I | emission | 4d9.(2D<3/2>).5s 2[3/2] → 4d9.(2D<5/2>).5p 2[7/2]* | Misurata | NIST | |
| 447.35846 nm | 180 | Pd I | emission | 4d9.(2D<3/2>).5s 2[3/2] → 4d9.(2D<5/2>).5p 2[3/2]* | Misurata | NIST | |
| 478.81874 nm | N/D | Pd I | emission | 4d9.(2D<5/2>).5p 2[3/2]* → 4d9.(2D<5/2>).5d 2[5/2] | Misurata | NIST | |
| 481.75067 nm | N/D | Pd I | emission | 4d9.(2D<5/2>).5p 2[3/2]* → 4d9.(2D<5/2>).5d 2[3/2] | Misurata | NIST | |
| 487.54251 nm | 35 | Pd I | emission | 4d9.(2D<5/2>).5p 2[3/2]* → 4d9.(2D<5/2>).5d 2[1/2] | Misurata | NIST | |
| 511.08092 nm | 55 | Pd I | emission | 4d9.(2D<5/2>).5p 2[7/2]* → 4d9.(2D<5/2>).5d 2[7/2] | Misurata | NIST | |
| 511.70072 nm | 75 | Pd I | emission | 4d9.(2D<3/2>).5p 2[5/2]* → 4d9.(2D<3/2>).5d 2[7/2] | Misurata | NIST | |
| 516.38405 nm | 160 | Pd I | emission | 4d9.(2D<5/2>).5p 2[7/2]* → 4d9.(2D<5/2>).5d 2[9/2] | Misurata | NIST | |
| 523.48612 nm | 55 | Pd I | emission | 4d9.(2D<5/2>).5p 2[7/2]* → 4d9.(2D<5/2>).5d 2[7/2] | Misurata | NIST | |
| 529.56266 nm | 120 | Pd I | emission | 4d9.(2D<5/2>).5p 2[7/2]* → 4d9.(2D<5/2>).5d 2[9/2] | Misurata | NIST | |
| 531.25867 nm | 18 | Pd I | emission | 4d9.(2D<5/2>).5p 2[3/2]* → 4d9.(2D<5/2>).5d 2[5/2] | Misurata | NIST | |
| 534.51048 nm | 15 | Pd I | emission | 4d9.(2D<3/2>).5p 2[5/2]* → 4d9.(2D<3/2>).5d 2[5/2] | Misurata | NIST | |
| 539.52204 nm | 35 | Pd I | emission | 4d9.(2D<3/2>).5p 2[5/2]* → 4d9.(2D<3/2>).5d 2[7/2] | Misurata | NIST | |
| 554.28067 nm | 55 | Pd I | emission | 4d9.(2D<5/2>).5p 2[5/2]* → 4d9.(2D<5/2>).5d 2[7/2] | Misurata | NIST | |
| 554.70204 nm | 35 | Pd I | emission | 4d9.(2D<5/2>).5p 2[5/2]* → 4d9.(2D<5/2>).5d 2[5/2] | Misurata | NIST | |
| 561.94631 nm | 27 | Pd I | emission | 4d9.(2D<3/2>).5p 2[3/2]* → 4d9.(2D<3/2>).5d 2[5/2] | Misurata | NIST | |
| 564.27039 nm | 15 | Pd I | emission | 4d9.(2D<3/2>).5p 2[1/2]* → 4d9.(2D<3/2>).5d 2[3/2] | Misurata | NIST | |
| 565.54366 nm | 14 | Pd I | emission | 4d9.(2D<3/2>).5p 2[3/2]* → 4d9.(2D<3/2>).5d 2[5/2] | Misurata | NIST | |
| 567.00702 nm | 75 | Pd I | emission | 4d9.(2D<5/2>).5p 2[5/2]* → 4d9.(2D<5/2>).5d 2[7/2] | Misurata | NIST | |
| 569.0128 nm | 11 | Pd I | emission | 4d9.(2D<3/2>).5p 2[1/2]* → 4d9.(2D<3/2>).5d 2[3/2] | Misurata | NIST | |
| 569.50921 nm | N/D | Pd I | emission | 4d9.(2D<5/2>).5p 2[5/2]* → 4d9.(2D<5/2>).5d 2[5/2] | Misurata | NIST | |
| 573.66175 nm | 18 | Pd I | emission | 4d9.(2D<5/2>).5p 2[5/2]* → 4d9.(2D<5/2>).5d 2[3/2] | Misurata | NIST | |
| 677.45174 nm | 23 | Pd I | emission | 4d8.5s2 3F → 4d9.(2D<3/2>).5p 2[5/2]* | Misurata | NIST | |
| 678.44893 nm | 65 | Pd I | emission | 4d9.(2D<5/2>).5p 2[3/2]* → 4d9.(2D<5/2>).6s 2[5/2] | Misurata | NIST | |
| 683.3446 nm | N/D | Pd I | emission | 4d9.(2D<3/2>).5p 2[3/2]* → 4d9.(2D<5/2>).5d 2[5/2] | Misurata | NIST | |
| 701.6446 nm | 11 | Pd I | emission | 4d9.(2D<3/2>).5p 2[1/2]* → 4d9.(2D<3/2>).6s 2[3/2] | Misurata | NIST | |
| 731.0053 nm | N/D | Pd I | emission | 4d9.(2D<3/2>).5p 2[5/2]* → 4d9.(2D<3/2>).6s 2[3/2] | Misurata | NIST | |
| 736.8096 nm | 75 | Pd I | emission | 4d9.(2D<5/2>).5p 2[7/2]* → 4d9.(2D<5/2>).6s 2[5/2] | Misurata | NIST | |
| 739.19 nm | 27 | Pd I | emission | 4d9.(2D<3/2>).5p 2[5/2]* → 4d9.(2D<3/2>).6s 2[3/2] | Misurata | NIST | |
| 748.6909 nm | 16 | Pd I | emission | 4d9.(2D<5/2>).5p 2[7/2]* → 4d9.(2D<5/2>).6s 2[5/2] | Misurata | NIST |
Proprietà estese
Raggi covalenti (dati estesi)
- Raggio covalente (Pyykkö)
- 120 pm
- Raggio covalente (Pyykkö, legame doppio)
- 117 pm
- Raggio covalente (Pyykkö, legame triplo)
- 112 pm
Raggi di van der Waals
- Batsanov
- 205 pm
- Alvarez
- 215 pm
- UFF
- 289,9 pm
- MM3
- 237 pm
Raggi atomici e metallici
- Raggio atomico (Rahm)
- 215 pm
- Raggio metallico (C12)
- 137 pm
Scale di numerazione
- Mendeleev
- 68
- Pettifor
- 69
- Glawe
- 65
Scale di elettronegatività
- Ghosh
- 0
- Miedema
- 5
- Gunnarsson–Lundqvist
- 3
- Robles–Bartolotti
- 2
Polarizzabilità e dispersione
- Polarizzabilità dipolare
- 26,14 a.u.
- Polarizzabilità dipolare (inc.)
- 0,1 a.u.
- C₆ (Gould–Bučko)
- 628 Ha·Bohr6
Affinità chimica
- Affinità protonica
- 696 kJ/mol
- Basicità in fase gassosa
- 673,4 kJ/mol
Parametri di Miedema
- Volume molare di Miedema
- 8,9 cm3/mol
- Densità elettronica di Miedema
- 5
Rischio di approvvigionamento ed economia
- Concentrazione della produzione
- 60
- Rischio relativo di approvvigionamento
- 8
- Distribuzione delle riserve
- 95
- Stabilità politica (principale produttore)
- 44
- Stabilità politica (principale detentore di riserve)
- 44
Transizioni di fase e allotropi
| Punto di fusione | 1827,95 K |
| Punto di ebollizione | 3236,15 K |
Categorie degli stati di ossidazione
Dati di riferimento avanzati
Costanti di schermaggio (9)
| n | Orbitale | 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 |
Dettaglio dei raggi cristallini (5)
| Carica | CN | Spin | rcrystal (pm) | Origine |
|---|---|---|---|---|
| 1 | II | 73 | ||
| 2 | IVSQ | 78 | ||
| 2 | VI | 100 | ||
| 3 | VI | 90 | ||
| 4 | VI | 75,5 | from r^3 vs V plots, |
Modalità di decadimento degli isotopi (62)
| Isotopo | Modalità | Intensità |
|---|---|---|
| 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% |
Fattori di diffusione dei raggi X (507)
| Energia (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 |
Dati aggiuntivi
Estimated Crustal Abundance
The estimated element abundance in the earth's crust.
1.5×10-2 milligrams per kilogram
Riferimenti (1)
- [5] Palladium https://education.jlab.org/itselemental/ele046.html
Estimated Oceanic Abundance
The estimated element abundance in the earth's oceans.
Not Applicable
Riferimenti (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.
Riferimenti (1)
- [6] Palladium https://periodic.lanl.gov/46.shtml
Riferimenti
(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.

