Hafnium (Hf)
transition-metalSolid
Masse atomique relative standard
178,49 uConfiguration électronique
[Xe] 6s2 4f14 5d2Point de fusion
2232,85 °CPoint d’ébullition
4602,85 °CMasse volumique
1,33e+4 kg/m³États d’oxydation
−2, 0, +1, +2, +3, +4Électronégativité (Pauling)
1,3Énergie d’ionisation (1re)
6,82507 eVAnnée de découverte
1911Rayon atomique
155 pmDétails
Hafnium is a dense, corrosion-resistant transition metal in group 4, chemically close to zirconium. It occurs almost entirely with zirconium minerals and is difficult to separate because the two elements have similar ionic sizes and chemistry. A defining technological feature is its very large thermal-neutron absorption cross section, which contrasts with zirconium's low absorption and makes high-purity separation important for nuclear applications.
Hafnium is a ductile metal with a brilliant silver luster. Its properties are considerably influenced by presence of zirconium impurities. Of all the elements, zirconium and hafnium are two of the most difficult to separate. Although their chemistry is almost identical, the density of zirconium is about half of hafnium. Very pure hafnium has been produced, with zirconium being the major impurity.
Hafnium has been successfully alloyed with iron, titanium, niobium, tantalum, and other metals. Hafnium carbide is the most refractory binary composition known, and the nitride is the most refractory of all known metal nitrides (m.p. 3310C). At 700 degrees C hafnium rapidly absorbs hydrogen to form the composition HfH1.86.
Hafnium is resistant to concentrated alkalis, but at elevated temperatures reacts with oxygen, nitrogen, carbon, boron, sulfur, and silicon. Halogens react directly to form tetrahalides.
The name derives from the Latin hafnia for Copenhagen. An element named celtium was erroneously claimed to have been discovered in 1911 by the French chemist Georges Urbain in rare earth samples, until the Danish physicist Niels Bohr, predicted hafnium's properties using his theory of electronic configuration of the elements. Bohr argued that hafnium would not be a rare earth element, but would be found in zirconium ore. Hafnium was discovered by the Dutch physicist Dirk Coster and the Hungarian physicist George von Hevesy in 1923, while working at Bohr's Institute in Copenhagen.
Hafnium was discovered by Dirk Coster, a Danish chemist, and George Charles de Hevesy, a Hungarian chemist, in 1923. They used a method known as X-ray spectroscopy to study the arrangement of the outer electrons of atoms in samples of zirconium ore. The electron structure of hafnium had been predicted by Niels Bohr and Coster and Hevesy found a pattern that matched. Hafnium is difficult to separate from zirconium and is present in all of its ores. It is obtained with the same methods used to extract zirconium.
From Hafinia, the Latin name for Copenhagen. Many years before its discovery in 1923 (credited to D. Coster and G. von Hevesey), Hafnium was thought to be present in various minerals and concentrations. On the basis of the Bohr theory, the new element was expected to be associated with zirconium.
It was finally identified in zircon from Norway, by means of X-ray spectroscope analysis. It was named in honor of the city in which the discovery was made. Most zirconium minerals contain 1 to 5 percent hafnium.
It was originally separated from zirconium by repeated recrystallization of the double ammonium or potassium fluorides by von Hevesey and Jantzen. Metallic hafnium was first prepared by van Arkel and deBoer by passing the vapor of the tetraiodide over a heated tungsten filament. Almost all hafnium metal now produced is made by reducing the tetrachloride with magnesium or with sodium (Kroll Process).
Pure hafnium is a lustrous, silvery-gray metal. It is solid and ductile under ordinary conditions and develops a thin protective oxide film in air. Finely divided hafnium can be much more reactive than bulk metal.
Hafnium is used chiefly where neutron absorption or high-temperature stability is valuable. Metallic hafnium is used in control rods and other neutron-absorbing components in some nuclear reactors. Hafnium-containing superalloys and refractory alloys can improve high-temperature strength and oxidation resistance. Hafnium dioxide, HfO₂, is used as a high-k dielectric material in semiconductor devices, replacing or supplementing silicon dioxide in advanced gate stacks. Hafnium compounds also appear in specialty ceramics, optical coatings, and catalysts, but these uses are smaller than zirconium-related industrial chemistry.
Hafnium is a good absorber of neutrons and is used in the control rods of nuclear reactors. Hafnium is also used in vacuum tubes as a getter, a material that combines with and removes trace gases from vacuum tubes. Hafnium has been used as an alloying agent in iron, titanium, niobium and other metals.
Melting near 3890°C, hafnium carbide (HfC) has the highest melting point of any known two-element compound. Hafnium nitride (HfN) also has a high melting point, around 3305°C. Other hafnium compounds include: hafnium chloride (HfCl4), hafnium fluoride (HfF4) and hafnium oxide (HfO2).
Because the element not only has a good absorption cross section for thermal neutrons (almost 600 times that of zirconium), but also excellent mechanical properties and is extremely corrosion-resistant, hafnium is used for reactor control rods. Such rods are used in nuclear submarines.
Hafnium is used in gas-filled and incandescent lamps, and is an efficient getter for scavenging oxygen and nitrogen.
Isotopes in Geochronology
Some 176Hf is radiogenic as a result of it being formed as a product of beta decay of radioactive 176Lu (half-life of 3.73×1010 years) [301] G. Faure. Principles of Isotope Geology, 2nd Edition. p. 608. Wiley, New York (1986).. Thus, relations between the isotope-amount ratiosn(176Hf)/n(177Hf) and n(176Hf)/n(176Lu) have been used to determine the ages of minerals and rocks. Because of the long half-life of 176Lu, these ratios have been used in geochronology studies that document some of the oldest rocks in the Solar System and on Earth (Fig. IUPAC.72.1).
Hafnium isotopic compositions of terrestrial materials evolved differently depending on the relative rates of 176Hf production. Geologists can use calculated lutetium-hafnium ages and the initial isotope-amount ratio n(176Hf)/n(177Hf) along with other isotopic data from the oldest rocks in the Earth to infer that the Earth’s crust differentiated within the first few hundred million years after condensation of the oldest solid matter in the Solar System [502] E. Scherer, C. Münker, K. Mezger. Science293, 683 (2001)..
Radioactive 182Hf decays to 182W with a half-life of 8.9×106 years, which is much less than the age of meteorites and the Earth. Therefore, measurements of the amounts of hafnium and tungsten isotopes in meteorites and terrestrial samples reveal the earlier presence of 182Hf. As a result, this provides information about chemical differentiation and evolution of the early Solar System [503] T. Kleine, M. Touboul, B. Bourdon, F. Nimmo, K. Mezger, H. Palme, S. B. Jacobsen, Q. Z. Yin, A. N. Halliday. Geochim. Cosmochim. Acta73, 5150 (2009)., [504] A. Schersten. Re-Os, Pt-Os and Hf-W Isotopes and Tracing the Core in Mantle Melts, MantlePlumes.org (2014), Feb. 25; http://www.mantleplumes.org/Os-W.html..
Hafnium chemistry is dominated by the +4 oxidation state, reflecting the stable Hf⁴⁺ ion and strong bonding to oxygen, halides, and other hard donor atoms. Hafnium dioxide, HfO₂, is a refractory, chemically durable oxide with high dielectric constant. Hafnium tetrachloride, HfCl₄, is a volatile moisture-sensitive chloride used in purification and chemical vapor or atomic layer deposition chemistry. Organometallic and amide precursors such as tetrakis(dimethylamido)hafnium, Hf[N(CH₃)₂]₄, are important for thin-film deposition. Lower oxidation states exist but are less common and often require specialized conditions.
See more information at the Hafnium compound page.
Bulk hafnium metal is generally of low acute chemical toxicity, but metal dust or powder can ignite and should be treated as a combustible solid. Hafnium compounds vary in hazard; soluble salts, halides, and organometallic precursors may be corrosive, moisture-sensitive, or toxic by inhalation or skin contact. Hafnium is not naturally radioactive in ordinary material, but reactor-exposed hafnium may contain activation products that require radiological control.
Finely divided hafnium is pyrophoric and can ignite spontaneously in air. Care should be taken when machining the metal or when handling hot sponge hafnium.
Hafnium is a trace lithophile element and follows zirconium in igneous rocks, sands, and resistant minerals. It is commonly hosted in zircon, ZrSiO₄, where hafnium substitutes for zirconium. The element has low mobility in most surface environments because its oxides and silicate-hosted forms are sparingly soluble. It has no known biological role, and environmental concentrations are normally controlled by the distribution and weathering resistance of zirconium minerals.
Hafnium is not usually mined as a primary product. It is recovered during the processing of zirconium minerals, especially when nuclear-grade zirconium is purified to remove neutron-absorbing impurities. Separation from zirconium is the central cost and supply constraint, commonly involving solvent extraction or related chemical fractionation followed by conversion to metal or compounds. Demand is concentrated in nuclear control materials, semiconductor precursors, and specialized high-temperature alloys. Supply is therefore tied to zirconium processing capacity and to the need for very low-hafnium zirconium in reactor fuel cladding, rather than to abundant independent hafnium ores.
Obtained from mineral zircon or baddeleyite.
Hafnium is a heavy element made mainly by neutron-capture processes in earlier generations of stars, with contributions from both slow and rapid neutron capture. It is far less abundant cosmically than lighter rock-forming elements. In planetary materials it behaves as a refractory lithophile element, condensing into high-temperature solids and concentrating with zirconium-bearing minerals rather than in metallic cores or volatile phases.
- Hafnium was one of the last stable elements to be identified in nature.
- Its name comes from Hafnia, the Latin name for Copenhagen.
- Zircon can contain enough hafnium to make separation important even when hafnium is not the desired product.
- Hafnium and zirconium are chemically so similar that early analytical work often missed hafnium.
- Hafnium carbide and tantalum hafnium carbide are noted for extremely high melting behavior.
Images
Propriétés
Propriétés physiques
- Rayon atomique (empirique)
- 155 pm Comparer : Rayon atomique (empirique) de tous les éléments →
- Rayon covalent
- 175 pm Comparer : Rayon covalent de tous les éléments →
- Rayon de van der Waals
- 212 pm Comparer : Rayon de van der Waals de tous les éléments →
- Rayon métallique
- 144 pm Comparer : Rayon métallique de tous les éléments →
- Masse volumique
- 1,33 × 104 kg/m³ Comparer : Masse volumique de tous les éléments →
- Volume molaire
- 0,0136 L/mol
- Phase aux CNTP
- Solide Comparer : Phase aux CNTP de tous les éléments →
- Point de fusion
- 2232,85 °C Comparer : Point de fusion de tous les éléments →
- Point d’ébullition
- 4602,85 °C Comparer : Point d’ébullition de tous les éléments →
- Conductivité thermique
- 23 W/(m·K) Comparer : Conductivité thermique de tous les éléments →
- Capacité thermique massique
- 0,144 J/(g·K) Comparer : Capacité thermique massique de tous les éléments →
- Capacité thermique molaire
- 25,73 J/(mol·K) Comparer : Capacité thermique molaire de tous les éléments →
- Structure cristalline
- Hexagonal compact Comparer : Structure cristalline de tous les éléments →
Propriétés chimiques
- Électronégativité (Pauling)
- 1,3 Comparer : Électronégativité (Pauling) de tous les éléments →
- Électronégativité (Allen)
- 1,16
- Affinité électronique
- 0,178 eV
- Énergie d’ionisation (1re)
- 6,82507 eV Comparer : Énergie d’ionisation (1re) de tous les éléments →
- Énergie d’ionisation (2e)
- 14,61005 eV Comparer : Énergie d’ionisation (2e) de tous les éléments →
- Énergie d’ionisation (3e)
- 22,550078 eV Comparer : Énergie d’ionisation (3e) de tous les éléments →
- Énergie d’ionisation (4e)
- 33,370115 eV Comparer : Énergie d’ionisation (4e) de tous les éléments →
- Énergie d’ionisation (5e)
- 68,370235 eV Comparer : Énergie d’ionisation (5e) de tous les éléments →
- États d’oxydation
- −2, 0, +1, +2, +3, +4 Comparer : États d’oxydation de tous les éléments →
- Électrons de valence
- 4 Comparer : Électrons de valence de tous les éléments →
- Configuration électronique
- [Xe] 6s2 4f14 5d2
Propriétés thermodynamiques
- Enthalpie de fusion
- 0,26667358 eV Comparer : Enthalpie de fusion de tous les éléments →
- Enthalpie de vaporisation
- 5,959476 eV Comparer : Enthalpie de vaporisation de tous les éléments →
- Enthalpie de sublimation
- 6,436234 eV
- Enthalpie d’atomisation
- 6,436234 eV
- Enthalpie d’atomisation
- 6,409286 eV
Propriétés nucléaires
- Protons
- 72 Comparer : Protons de tous les éléments →
- Neutrons
- 108 Comparer : Neutrons de tous les éléments →
- Isotopes connus
- 38 Comparer : Isotopes connus de tous les éléments →
- Isotopes stables
- 4 Comparer : Isotopes stables de tous les éléments →
- Isotope le plus stable
- Hf-180
- Année de découverte
- 1911
Abondance
- Abondance (croûte terrestre)
- 3 mg/kg Comparer : Abondance (croûte terrestre) de tous les éléments →
- Abondance (océan)
- 7 × 10−6 mg/L Comparer : Abondance (océan) de tous les éléments →
Structure cristalline
- Paramètre de maille a
- 320 pm
Structure électronique
- Électrons par couche
- 2, 8, 18, 32, 10, 2 Comparer : Électrons par couche de tous les éléments →
Identifiants
- Numéro CAS
- 7440-58-6 Comparer : Numéro CAS de tous les éléments →
- Symbole de terme
- 3F2
- InChI
- InChI=1S/Hf
- Clé InChI
- VBJZVLUMGGDVMO-UHFFFAOYSA-N
Configuration électronique Mesuré
Hf: 4f¹⁴ 5d² 6s²[Xe] 4f¹⁴ 5d² 6s²1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 4f¹⁴ 5d² 6s²Modèle atomique
Les isotopes diffèrent par leur nombre de neutrons, leur masse et leur stabilité — pas par la configuration électronique de l’atome neutre.
Modèle atomique schématique, non à l’échelle.
Empreinte atomique
Spectre d’émission / d’absorption
Distribution isotopique
| Nombre de masse | Masse atomique (u) | Abondance naturelle | Demi-vie |
|---|---|---|---|
| 176 Stable | 175,9414076 ± 0,0000022 | 5,2600% | Stable |
| 178 Stable | 177,9437058 ± 0,000002 | 27,2800% | Stable |
| 179 Stable | 178,9458232 ± 0,000002 | 13,6200% | Stable |
| 180 Stable | 179,946557 ± 0,000002 | 35,0800% | Stable |
Phase / État
Explication: 2207,8 °C en dessous du point de fusion (2232,85 °C)
Schématique, non à l’échelle
Points de transition de phase
Énergies de transition
Énergie nécessaire pour faire fondre 1 mol au point de fusion
Énergie nécessaire pour vaporiser 1 mol au point d’ébullition
Énergie nécessaire pour sublimer 1 mol au point de sublimation
Masse volumique
Dans les conditions standard
Dans les conditions standard
Spectres atomiques
Affichage de 10 sur 72. Tri par charge ionique croissante.
Raies répertoriées ?
| Ion | Charge | Nombre total de raies | Probabilités de transition | Désignations des niveaux |
|---|---|---|---|---|
| Hf I | 0 | 5341 | 187 | 3821 |
| Hf II | +1 | 218 | 2 | 10 |
| Hf III | +2 | 37 | 0 | 0 |
| Hf IV | +3 | 27 | 0 | 0 |
| Hf V | +4 | 82 | 0 | 0 |
Niveaux répertoriés ?
| Ion | Charge | Niveaux |
|---|---|---|
| Hf I | 0 | 333 |
| Hf II | +1 | 125 |
| Hf III | +2 | 2 |
| Hf IV | +3 | 2 |
| Hf V | +4 | 2 |
| Hf VI | +5 | 2 |
| Hf VII | +6 | 2 |
| Hf VIII | +7 | 2 |
| Hf IX | +8 | 2 |
| Hf X | +9 | 2 |
Rayons ioniques
| Charge | Coordinence | Spin | Rayon |
|---|---|---|---|
| +4 | 4 | N/D | 57.99999999999999 pm |
| +4 | 6 | N/D | 71 pm |
| +4 | 7 | N/D | 76 pm |
| +4 | 8 | N/D | 83 pm |
Composés
Isotopes (4)
| Nombre de masse | Masse atomique (u) | Abondance naturelle | Demi-vie | Mode de désintégration | |
|---|---|---|---|---|---|
| 176 Stable | 175,9414076 ± 0,0000022 | 5,2600% ± 0,0700% | Stable | stable | |
| 178 Stable | 177,9437058 ± 0,000002 | 27,2800% ± 0,0700% | Stable | stable | |
| 179 Stable | 178,9458232 ± 0,000002 | 13,6200% ± 0,0200% | Stable | stable | |
| 180 Stable | 179,946557 ± 0,000002 | 35,0800% ± 0,1600% | Stable | stable |
Raies spectrales
Affichage de 50 sur 1890. Seules les raies spectrales dont l’intensité a été mesurée sont affichées par défaut.
| Longueur d’onde (nm) | Intensité | Degré d’ionisation | Type | Transition | Précision | Source | |
|---|---|---|---|---|---|---|---|
| 417.433998 nm | 48000 | Hf I | emission | 5d2.6s2 a 3F → 5d2.(a 3F).6s.(a 4F).6p z 5D* | Mesurée | NIST | |
| 380.03629 nm | 36000 | Hf I | emission | 5d2.6s2 a 3F → 5d2.(a 3F).6s.(a 4F).6p z 5D* | Mesurée | NIST | |
| 382.072307 nm | 34000 | Hf I | emission | 5d2.6s2 a 3F → 5d2.(a 3F).6s.(a 4F).6p y 3F* | Mesurée | NIST | |
| 723.71003 nm | 34000 | Hf I | emission | 5d2.6s2 a 3F → 5d.6s2.(a 2D).6p z 3D* | Mesurée | NIST | |
| 384.917811 nm | 32000 | Hf I | emission | 5d2.6s2 a 1D → 5d2.(a 3F).6s.(a 2F).6p y 1D* | Mesurée | NIST | |
| 713.1807 nm | 32000 | Hf I | emission | 5d2.6s2 a 3F → 5d.6s2.(a 2D).6p z 3D* | Mesurée | NIST | |
| 389.993003 nm | 29000 | Hf I | emission | 5d2.6s2 a 3F → 5d2.(a 3F).6s.(a 4F).6p z 5D* | Mesurée | NIST | |
| 395.181289 nm | 26000 | Hf I | emission | 5d2.6s2 a 3F → 5d2.(a 3F).6s.(a 4F).6p y 3F* | Mesurée | NIST | |
| 385.830632 nm | 25000 | Hf I | emission | 5d2.6s2 a 3F → 5d2.(a 3F).6s.(a 4F).6p y 3D* | Mesurée | NIST | |
| 724.0873 nm | 21000 | Hf I | emission | 5d2.6s2 a 3F → 5d.6s2.(a 2D).6p z 3D* | Mesurée | NIST | |
| 393.137246 nm | 19000 | Hf I | emission | 5d2.6s2 a 3F → 5d2.(a 3F).6s.(a 4F).6p y 3D* | Mesurée | NIST | |
| 480.049829 nm | 17000 | Hf I | emission | 5d2.6s2 a 1D → 5d.6s2.(a 2D).6p z 1P* | Mesurée | NIST | |
| 397.347912 nm | 15000 | Hf I | emission | 5d2.6s2 a 3F → 5d2.(a 3F).6s.(a 4F).6p z 5D* | Mesurée | NIST | |
| 706.38474 nm | 15000 | Hf I | emission | 5d2.6s2 a 1D → 5d.6s2.(a 2D).6p z 3P* | Mesurée | NIST | |
| 381.177553 nm | 14000 | Hf I | emission | 5d2.6s2 a 3F → 5d2.(a 3F).6s.(a 4F).6p z 3G* | Mesurée | NIST | |
| 555.06011 nm | 14000 | Hf I | emission | 5d2.6s2 a 3F → 5d2.(a 3F).6s.(a 4F).6p z 5G* | Mesurée | NIST | |
| 555.211884 nm | 14000 | Hf I | emission | 5d2.6s2 a 1D → 5d.6s2.(a 2D).6p z 1F* | Mesurée | NIST | |
| 456.593715 nm | 13000 | Hf I | emission | 5d2.6s2 a 1D → 5d2.(a 3P).6s.(a 4P).6p y 5D* | Mesurée | NIST | |
| 435.630591 nm | 12000 | Hf I | emission | 5d2.6s2 a 3F → 5d2.(a 3F).6s.(a 4F).6p z 5D* | Mesurée | NIST | |
| 445.734411 nm | 12000 | Hf I | emission | 5d2.6s2 a 3F → 5d2.(a 3F).6s.(a 4F).6p z 5F* | Mesurée | NIST | |
| 459.87979 nm | 12000 | Hf I | emission | 5d2.6s2 a 3F → 5d2.(a 3F).6s.(a 4F).6p z 5F* | Mesurée | NIST | |
| 462.086529 nm | 12000 | Hf I | emission | 5d2.6s2 a 3F → 5d2.(a 3F).6s.(a 4F).6p z 5F* | Mesurée | NIST | |
| 465.518924 nm | 12000 | Hf I | emission | 5d2.6s2 a 3P → 5d2.(a 3P).6s.(a 4P).6p z 3S* | Mesurée | NIST | |
| 380.044548 nm | 11000 | Hf I | emission | 5d2.6s2 a 1D → 5d2.(a 3P).6s.(a 4P).6p z 5S* | Mesurée | NIST | |
| 429.477692 nm | 11000 | Hf I | emission | 5d2.6s2 a 3F → 5d2.(a 3F).6s.(a 4F).6p z 5D* | Mesurée | NIST | |
| 681.89395 nm | 11000 | Hf I | emission | 5d2.6s2 a 3P → 5d.6s2.(a 2D).6p z 1F* | Mesurée | NIST | |
| 396.799621 nm | 10000 | Hf I | emission | 5d2.6s2 a 3F → 5d2.(a 3F).6s.(a 4F).6p z 5D* | Mesurée | NIST | |
| 406.28356 nm | 10000 | Hf I | emission | 5d.6s2.(a 2D).6p z 1D* → 3512 | Mesurée | NIST | |
| 497.525232 nm | 10000 | Hf I | emission | 5d2.6s2 a 3F → 5d2.(a 3F).6s.(a 4F).6p z 5F* | Mesurée | NIST | |
| 454.093108 nm | 8400 | Hf I | emission | 5d2.6s2 a 1D → 5d2.(a 3F).6s.(a 4F).6p y 3F* | Mesurée | NIST | |
| 443.80364 nm | 8300 | Hf I | emission | 5d2.6s2 a 3P → 5d2.(a 3P).6s.(a 4P).6p z 3S* | Mesurée | NIST | |
| 446.117576 nm | 8300 | Hf I | emission | 5d2.6s2 a 1D → 5d2.(a 3P).6s.(a 4P).6p z 3S* | Mesurée | NIST | |
| 459.891547 nm | 8300 | Hf I | emission | 5d2.6s2 a 3F → 5d2.(a 3F).6s.(a 4F).6p z 5D* | Mesurée | NIST | |
| 408.33549 nm | 8000 | Hf I | emission | 5d.6s2.(a 2D).6p z 1D* → 3499 | Mesurée | NIST | |
| 571.91718 nm | 7300 | Hf I | emission | 5d2.6s2 a 3P → 5d.6s2.(a 2D).6p z 1P* | Mesurée | NIST | |
| 403.225898 nm | 7200 | Hf I | emission | 5d2.6s2 a 3F → 5d2.(a 3F).6s.(a 4F).6p y 3F* | Mesurée | NIST | |
| 478.27405 nm | 7100 | Hf I | emission | 5d.6s2.(a 2D).6p z 3F* → 6p2.(3P).5d.(2D).6s c 3D | Mesurée | NIST | |
| 383.001314 nm | 6700 | Hf I | emission | 5d3.(b 4F).6s a 5F → 5d2.(b 1D).6s.(b 2D).6p v 3F* | Mesurée | NIST | |
| 504.743848 nm | 6500 | Hf I | emission | 5d2.6s2 a 3P → 5d2.(a 3F).6s.(a 4F).6p y 3D* | Mesurée | NIST | |
| 485.92338 nm | 6400 | Hf I | emission | 5d.6s2.(a 2D).6p z 3F* → 3512 | Mesurée | NIST | |
| 386.09058 nm | 6300 | Hf I | emission | 5d2.6s2 a 3P → 5d2.(a 3F).6s.(a 2F).6p y 1F* | Mesurée | NIST | |
| 441.790242 nm | 6200 | Hf I | emission | 5d2.6s2 a 1D → 5d2.(a 3F).6s.(a 4F).6p y 3D* | Mesurée | NIST | |
| 388.935622 nm | 5900 | Hf I | emission | 5d2.6s2 a 1D → 5d2.(a 3P).6s.(a 4P).6p y 5D* | Mesurée | NIST | |
| 469.90048 nm | 5900 | Hf I | emission | 5d2.(a 3F).6s.(a 4F).6p z 5G* → 5d2.(3F).6s.(a 4F).7s b 5F | Mesurée | NIST | |
| 678.92714 nm | 5900 | Hf I | emission | 5d2.6s2 a 3F → 5d2.(a 3F).6s.(a 4F).6p z 5G* | Mesurée | NIST | |
| 433.027751 nm | 5800 | Hf I | emission | 5d2.6s2 a 3F → 5d2.(a 3F).6s.(a 4F).6p y 3F* | Mesurée | NIST | |
| 410.65431 nm | 5600 | Hf I | emission | 5d2.6s2 a 1G → 5d2.(a 3F).6s.(a 2F).6p y 1F* | Mesurée | NIST | |
| 426.34428 nm | 5400 | Hf I | emission | 5d2.6s2 a 3F → 5d2.(a 3F).6s.(a 4F).6p z 5F* | Mesurée | NIST | |
| 477.37157 nm | 5400 | Hf I | emission | 5d2.6s2 a 3P → 5d.6s2.(a 2D).6p z 1P* | Mesurée | NIST | |
| 590.29382 nm | 5400 | Hf I | emission | 5d2.6s2 a 3F → 5d2.(a 3F).6s.(a 4F).6p z 5G* | Mesurée | NIST |
Propriétés étendues
Rayons covalents (données étendues)
- Rayon covalent (Pyykkö)
- 152 pm
- Rayon covalent (Pyykkö, liaison double)
- 128 pm
- Rayon covalent (Pyykkö, liaison triple)
- 122 pm
Rayons de van der Waals
- Batsanov
- 225 pm
- Alvarez
- 263 pm
- UFF
- 314,1 pm
- MM3
- 253 pm
Rayons atomiques et métalliques
- Rayon atomique (Rahm)
- 264 pm
- Rayon métallique (C12)
- 159 pm
Échelles de numérotation
- Mendeleev
- 45
- Pettifor
- 50
- Glawe
- 50
Échelles d’électronégativité
- Ghosh
- 0
- Miedema
- 4
- Gunnarsson–Lundqvist
- 5
- Robles–Bartolotti
- 4
Polarisabilité et dispersion
- Polarisabilité dipolaire
- 103 a.u.
- Polarisabilité dipolaire (incertitude)
- 6 a.u.
- C₆ (Gould–Bučko)
- 1040 Ha·Bohr6
Paramètres de Miedema
- Volume molaire de Miedema
- 13,45 cm3/mol
- Densité électronique de Miedema
- 3
Transitions de phase et allotropes
| Point de fusion | 2506,15 K |
| Point d’ébullition | 4873,15 K |
Catégories d’états d’oxydation
Données de référence avancées
Constantes d’écran (14)
| n | Orbitale | σ |
|---|---|---|
| 1 | s | 1,3984 |
| 2 | p | 4,4012 |
| 2 | s | 18,8102 |
| 3 | d | 13,5702 |
| 3 | p | 21,0168 |
| 3 | s | 21,6885 |
| 4 | d | 36,476 |
| 4 | f | 39,7904 |
| 4 | p | 34,0704 |
| 4 | s | 33,0228 |
Détail des rayons cristallins (4)
| Charge | CN | Spin | rcrystal (pm) | Origine |
|---|---|---|---|---|
| 4 | IV | 72 | from r^3 vs V plots, | |
| 4 | VI | 85 | from r^3 vs V plots, | |
| 4 | VII | 90 | ||
| 4 | VIII | 97 |
Modes de désintégration des isotopes (46)
| Isotope | Mode | Intensité |
|---|---|---|
| 153 | B+ | — |
| 154 | B+ | 100% |
| 154 | A | 0% |
| 155 | B+ | 100% |
| 155 | A | — |
| 156 | A | 100% |
| 156 | B+ | — |
| 157 | A | 94% |
| 157 | B+ | 14% |
| 158 | B+ | 55,7% |
Facteurs de diffusion des rayons X (514)
| Énergie (eV) | f₁ | f₂ |
|---|---|---|
| 10 | — | 2,62338 |
| 10,1617 | — | 2,71485 |
| 10,3261 | — | 2,80951 |
| 10,4931 | — | 2,90326 |
| 10,6628 | — | 2,98247 |
| 10,8353 | — | 3,06384 |
| 11,0106 | — | 3,14744 |
| 11,1886 | — | 3,21346 |
| 11,3696 | — | 3,27509 |
| 11,5535 | — | 3,33789 |
Données complémentaires
Estimated Crustal Abundance
The estimated element abundance in the earth's crust.
3.0 milligrams per kilogram
Références (1)
Estimated Oceanic Abundance
The estimated element abundance in the earth's oceans.
7×10-6 milligrams per liter
Références (1)
Références
(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 Hafnium.
The element property data was retrieved from publications.