|Named after||Joseph von Fraunhofer|
|Name in Saurian|| Vhuidxevohaim (Vx)|
|Systematic name|| Unhexunium (Uhn)|
|Location on the periodic table|
|Element above Fraunhoferium||Bohrium|
|Element left of Fraunhoferium||Hundium|
|Element right of Fraunhoferium||Madelungium|
|465.8680 u, 773.5919 yg|
|Atomic radius||199 pm, 1.99 Å|
|Covalent radius||201 pm, 2.01 Å|
|van der Waals radius||238 pm, 2.38 Å|
|s||462 (161 p+, 301 no)|
|Electron configuration||[Og] 5g18 6f14 7d6 8s2 8p2 9s1|
|Electrons per shell||2, 8, 18, 32, 50, 32, 14, 4, 1|
|Oxidation states|| −1, 0, +1, +2, +3, +4,|
+5, +6, +7, +8, +9
(a strongly basic oxide)
|First ionization energy||475.8 kJ/mol, 4.931 eV|
|Electron affinity||34.9 kJ/mol, 0.362 eV|
|Molar mass||465.868 g/mol|
|Molar volume||11.617 cm3/mol|
|Atomic number density|| 1.29 × 1021 g−1|
5.18 × 1022 cm−3
|Average atomic separation||268 pm, 2.68 Å|
|Crystal structure||Body-centered cubic|
|Melting point|| 682.60 K, 1228.68°R|
|Boiling point|| 2604.95 K, 4668.91°R|
|Liquid range||1922.35 , 3460.24|
|Triple point|| 682.61 K, 1228.69°R|
@ 133.58 nPa, 1.0019 × 10−9 torr
|Critical point|| 7752.17 K, 13953.91°R|
@ 78.0914 MPa, 770.704 atm
|Heat of fusion||6.014 kJ/mol|
|Heat of vaporization||221.291 kJ/mol|
|Heat capacity|| 0.05715 J/(g• ), 0.10287 J/(g• )|
26.626 J/(mol• ), 47.926 J/(mol• )
|Abundance in the universe|
|By mass|| Relative: 6.74 × 10−31|
Absolute: 2.26 × 1022 kg
|By atom||3.80 × 10−32|
Fraunhoferium is the provisional non-systematic name of a theoretical element with the symbol Fh and atomic number 161. Fraunhoferium was named in honor of Joseph von Fraunhofer (1787–1826), who revolutionized spectroscopy by discovering dark absorption lines on the spectrum, which are fingerprints for identifying elements or compounds. This element is known in the scientific literature as unhexunium (Uhu), dvi-rhenium, or simply element 161. Fraunhoferium is the heaviest member of the manganese family (below manganese, technetium, rhenium, and bohrium) and is the fifth member of the kelvinide series; this element is located in the periodic table coordinate 7d5.
Atomic properties Edit
Fraunhoferium's atom masses 465.868 daltons; the mass of the nucleus is just barely less than the mass of the atom at 465.780 daltons. The nucleus is comprised of 161 protons and 301 neutrons, corresponding to its nuclear ratio of 1.87, meaning the atom has 1.87 neutrons per proton.
There are 161 electrons in 25 orbitals (9 shells). The electron configuration is [Og] 5g18 6f14 7d6 8s2 8p2 9s1, strongly disagreeing with the element's placement on the periodic table. Notice that there is one electron in the ninth shell even though it is not a period 9 element because of the extreme relativistic effects causing high spin-orbit coupling, leaving 7d orbital with just six instead of seven electrons.
Like every other trans-lead elements, fraunhoferium has no stable isotopes. The longest-lived isotope is 462Fh with a half-life (t½) of 87 seconds. It undergoes spontaneous fission, splitting into two or three lighter nuclei plus neutrons like the examples.
464Fh has a half-life of 2.36 seconds. Like most elements, fraunhoferium has several meta states with half-lives of at least a nanosecond. The most stable metastable fraunhoferium isotope is 461m3Fh, whose half-life is as long as three days, 461m2Fh two hours, and 461m1Fh three kiloseconds. Like the parent ground state isotope whose fission half-life is just 1.46 seconds, they all undergo spontaneous fission.
Chemical properties and compounds Edit
Since fraunhoferium lies below other manganese family members, its chemistry should resemble other members like manganese and iridium. But however due to an electron in the 9s orbital due to spin-orbit coupling, fraunhoferium would instead behave much more like an alkali metal than a transition metal, thus making fraunhoferium very reactive unlike other members of the group. For lighter cogeners, electronegativities and ionization energies increase the further down in the group goes, but there is a sudden drop-off at fraunhoferium. Its electronegativity is 0.88 and first ionization energy is 4.93 eV, for comparison manganese has the electronegativity of 1.88 and first ionization energy 7.64 eV, both second lowest to fraunhoferium. Fraunhoferium can form many stable trivalent compounds with a +3 oxidation state. It can form ionic bonds with nonmetals, such as fluorine (FhF3), chlorine (FhCl3), and oxygen (Fh2O3). These compounds would have high melting and boiling points due to the strength of ionic bonds. Also, fraunhoferium forms colorless +3 ions (Fh3+) in aqueous solutions.
FhF3 and FhCl3 are white ionic salts similar in appearance to NaCl. Other trihalides are FhBr3 and FhI3, both yellow ionic salts. Fraunhoferium loses greenish color when exposed to air to form a brownish black Fh2O3. Fh2O7 can be created when the metal or suboxide is heated slightly with pure oxygen. It is a vivid red powder that decomposes at 1454°F (1063 K). The sulfur homologues of oxides are Fh2S3 and Fh2S7, which are white and bright amber-colored powder, respectively. Fh4C3, Fh4C, and FhC are refractory gray semiconducting solids, as well as corresponding silicides.
Fraunhoferium can form neutral salts like Fh2SiO3 and Fh2CO3 when the metal dissolves in silicic acid and carbonic acid, respectively. Fraunhoferium hydroxide, Fh(OH)3, is obtained when the metal reacts vigorously with water. Unlike typical transition metal hydroxides, which are weak bases, Fh(OH)3 is a very strong base like NaOH.
It can also form organic compounds called organofraunhoferium compounds like fraunhoferium sugars and fraunhoferium alcohols. Like inorganic compounds, +1 oxistate is predominant in organic compounds. For example, fraunhoferium replaces hydrogen atom in sucrose to make C12H21O11Fh (fraunhoferium sucrose), while it replaces hydrogen atom in ethane or hydroxide in ethanol to make C2H5Fh (monoethylfraunhoferium). These compounds are similar in appearance to corresponding ordinary compounds.
Physical properties Edit
Unlike most metals, fraunhoferium is not silvery, but a dark green metal, caused by the interactions of electrons in the s- and d-orbitals oscillating weakly at wavelengths in the green region of the spectrum. Fraunhoferium is solid up to 769°F (683 K), and be gaseous above 4229°F (2605 K). It is very dense, densing at 40 g/cm3, quince the density of iron. The atoms arrange to form body-centered cubic crystal lattices with an average separation of 268 pm.
It is almost certain that fraunhoferium doesn't exist on Earth at all, but it is believe to barely exist somewhere in the universe due to its brief lifetime. Every element heavier than iron can only naturally be produced by exploding stars. But it is likely impossible for even the most powerful supernovae or most violent neutron star collisions to produce this element through r-process because there's not enough energy available or not enough neutrons, respectively, to produce this hyperheavy element. Instead, this element can only be produced by advanced technological civilizations, virtually accounting for all of its abundance in the universe. An estimated abundance of fraunhoferium in the universe by mass is 6.74 × 10−31, which amounts to 2.26 × 1022 kilograms, which is just under a third of our moon in resource of this element.
To synthesize most stable isotopes of fraunhoferium, nuclei of a couple lighter elements must be fused together, and right amount of neutrons must be seeded. This operation would be impossible using current technology since it requires a tremendous amount of energy, thus its cross section would be so low that it is beyond the technological limit. Even if synthesis succeeds, this resulting element would quickly undergo fission. Here's couple of example equations in the synthesis of the most stable isotope, 462Fh.