User:Praseodymium-141/Lanthanide compounds: Difference between revisions
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=== Tetraborides === |
=== Tetraborides === |
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Tetraborides, LnB<sub>4</sub> have been reported for all of the lanthanides except EuB<sub>4</sub>, all have the same UB<sub>4</sub> [[yttrium borides#YB4 (yttrium tetraboride)|structure]]. The structure has a boron sub-lattice consists of chains of octahedral B<sub>6</sub> clusters linked by boron atoms. The unit cell decreases in size successively from LaB<sub>4</sub> to LuB<sub>4</sub>. The tetraborides of the lighter lanthanides melt with decomposition to LnB<sub>6</sub>.<ref name = "InorgReactvol13"/> Attempts to make EuB<sub>4</sub> have failed.<ref name = "Alper"/> The LnB<sub>4</sub> are good conductors<ref name="Mori handbookvol38"/> and typically antiferromagnetic.<ref name = "Atwood"/> |
Tetraborides, LnB<sub>4</sub>, have been reported for all of the lanthanides except EuB<sub>4</sub>, all have the same UB<sub>4</sub> [[yttrium borides#YB4 (yttrium tetraboride)|structure]]. The structure has a boron sub-lattice consists of chains of octahedral B<sub>6</sub> clusters linked by boron atoms. The unit cell decreases in size successively from LaB<sub>4</sub> to LuB<sub>4</sub>. The tetraborides of the lighter lanthanides melt with decomposition to LnB<sub>6</sub>.<ref name = "InorgReactvol13"/> Attempts to make EuB<sub>4</sub> have failed.<ref name = "Alper"/> The LnB<sub>4</sub> are good conductors<ref name="Mori handbookvol38"/> and typically antiferromagnetic.<ref name = "Atwood"/> |
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=== Hexaborides === |
=== Hexaborides === |
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Hexaborides, LnB<sub>6</sub> have been reported for all of the lanthanides. They all have the CaB<sub>6</sub> [[yttrium borides#YB6 (yttrium hexaboride)|structure]], containing B<sub>6</sub> clusters. They are non-stoichiometric due to cation defects. The hexaborides of the lighter lanthanides (La – Sm) melt without decomposition, EuB<sub>6</sub> decomposes to boron and metal and the heavier lanthanides decompose to LnB<sub>4</sub> with exception of YbB<sub>6</sub> which decomposes forming YbB<sub>12</sub>. The stability has in part been correlated to differences in volatility between the lanthanide metals.<ref name = "InorgReactvol13"/> In EuB<sub>6</sub> and YbB<sub>6</sub> the metals have an oxidation state of +2 whereas in the rest of the lanthanide hexaborides it is +3. This rationalises the differences in conductivity, the extra electrons in the Ln<sup>III</sup> hexaborides entering conduction bands. EuB<sub>6</sub> is a semiconductor and the rest are good conductors.<ref name = "Atwood"/><ref name = "InorgReactvol13"/> [[lanthanum hexaboride|LaB<sub>6</sub>]] and [[cerium hexaboride|CeB<sub>6</sub>]] are thermionic emitters, used, for example, in [[scanning electron microscope]]s.<ref>{{cite book|author=Reimer, Ludwig |title=Image Formation in Low-voltage Scanning Electron Microscopy|url=https://books.google.com/books?id=BbUO-gwN00AC&pg=PR9|year=1993|publisher=SPIE Press|isbn=978-0-8194-1206-5}}</ref> |
Hexaborides, LnB<sub>6</sub>, have been reported for all of the lanthanides. They all have the CaB<sub>6</sub> [[yttrium borides#YB6 (yttrium hexaboride)|structure]], containing B<sub>6</sub> clusters. They are non-stoichiometric due to cation defects. The hexaborides of the lighter lanthanides (La – Sm) melt without decomposition, EuB<sub>6</sub> decomposes to boron and metal and the heavier lanthanides decompose to LnB<sub>4</sub> with exception of YbB<sub>6</sub> which decomposes forming YbB<sub>12</sub>. The stability has in part been correlated to differences in volatility between the lanthanide metals.<ref name = "InorgReactvol13"/> In EuB<sub>6</sub> and YbB<sub>6</sub> the metals have an oxidation state of +2 whereas in the rest of the lanthanide hexaborides it is +3. This rationalises the differences in conductivity, the extra electrons in the Ln<sup>III</sup> hexaborides entering conduction bands. EuB<sub>6</sub> is a semiconductor and the rest are good conductors.<ref name = "Atwood"/><ref name = "InorgReactvol13"/> [[lanthanum hexaboride|LaB<sub>6</sub>]] and [[cerium hexaboride|CeB<sub>6</sub>]] are thermionic emitters, used, for example, in [[scanning electron microscope]]s.<ref>{{cite book|author=Reimer, Ludwig |title=Image Formation in Low-voltage Scanning Electron Microscopy|url=https://books.google.com/books?id=BbUO-gwN00AC&pg=PR9|year=1993|publisher=SPIE Press|isbn=978-0-8194-1206-5}}</ref> |
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=== Dodecaborides === |
=== Dodecaborides === |
Revision as of 17:24, 22 April 2024
Lanthanide compounds are compounds formed by the 15 elements classed as lanthanides. The lanthanides are generally trivalent, although some, such as cerium and europium, are capable of forming compounds in other oxidation states.[1]
Hydrides
Chemical element | La | Ce | Pr | Nd | Pm | Sm | Eu | Gd | Tb | Dy | Ho | Er | Tm | Yb | Lu |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Atomic number | 57 | 58 | 59 | 60 | 61 | 62 | 63 | 64 | 65 | 66 | 67 | 68 | 69 | 70 | 71 |
Metal lattice (RT) | dhcp | fcc | dhcp | dhcp | dhcp | r | bcc | hcp | hcp | hcp | hcp | hcp | hcp | hcp | hcp |
Dihydride[2] | LaH2+x | CeH2+x | PrH2+x | NdH2+x | SmH2+x | EuH2 o "salt like" |
GdH2+x | TbH2+x | DyH2+x | HoH2+x | ErH2+x | TmH2+x | YbH2+x o, fcc "salt like" |
LuH2+x | |
Structure | CaF2 | CaF2 | CaF2 | CaF2 | CaF2 | CaF2 | *PbCl2[3] | CaF2 | CaF2 | CaF2 | CaF2 | CaF2 | CaF2 | CaF2 | |
metal sub lattice | fcc | fcc | fcc | fcc | fcc | fcc | o | fcc | fcc | fcc | fcc | fcc | fcc | o fcc | fcc |
Trihydride[2] | LaH3−x | CeH3−x | PrH3−x | NdH3−x | SmH3−x | EuH3−x[4] | GdH3−x | TbH3−x | DyH3−x | HoH3−x | ErH3−x | TmH3−x | LuH3−x | ||
metal sub lattice | fcc | fcc | fcc | hcp | hcp | hcp | fcc | hcp | hcp | hcp | hcp | hcp | hcp | hcp | hcp |
Trihydride properties transparent insulators (color where recorded) |
red | bronze to grey[5] | PrH3−x fcc | NdH3−x hcp | golden greenish[6] | EuH3−x fcc | GdH3−x hcp | TbH3−x hcp | DyH3−x hcp | HoH3−x hcp | ErH3−x hcp | TmH3−x hcp | LuH3−x hcp |
Halides
Chemical element | La | Ce | Pr | Nd | Pm | Sm | Eu | Gd | Tb | Dy | Ho | Er | Tm | Yb | Lu |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Atomic number | 57 | 58 | 59 | 60 | 61 | 62 | 63 | 64 | 65 | 66 | 67 | 68 | 69 | 70 | 71 |
Tetrafluoride | CeF4 | PrF4 | NdF4 | TbF4 | DyF4 | ||||||||||
Color m.p. °C | white dec | white dec | white dec | ||||||||||||
Structure C.N. | UF4 8 | UF4 8 | UF4 8 | ||||||||||||
Trifluoride | LaF3 | CeF3 | PrF3 | NdF3 | PmF3 | SmF3 | EuF3 | GdF3 | TbF3 | DyF3 | HoF3 | ErF3 | TmF3 | YbF3 | LuF3 |
Color m.p. °C | white 1493[11] | white 1430 | green 1395 | violet 1374 | green 1399 | white 1306 | white 1276 | white 1231 | white 1172 | green 1154 | pink 1143 | pink 1140 | white 1158 | white 1157 | white 1182 |
Structure C.N. | LaF3 9 | LaF3 9 | LaF3 9 | LaF3 9 | LaF3 9 | YF3 8 | YF3 8 | YF3 8 | YF3 8 | YF3 8 | YF3 8 | YF3 8 | YF3 8 | YF3 8 | YF3 8 |
Trichloride | LaCl3 | CeCl3 | PrCl3 | NdCl3 | PmCl3 | SmCl3 | EuCl3 | GdCl3 | TbCl3 | DyCl3 | HoCl3 | ErCl3 | TmCl3 | YbCl3 | LuCl3 |
Color m.p. °C | white 858 | white 817 | green 786 | mauve 758 | green 786 | yellow 682 | yellow dec | white 602 | white 582 | white 647 | yellow 720 | violet 776 | yellow 824 | white 865 | white 925 |
Structure C.N. | UCl3 9 | UCl3 9 | UCl3 9 | UCl3 9 | UCl3 9 | UCl3 9 | UCl3 9 | UCl3 9 | PuBr3 8 | PuBr3 8 | YCl3 6 | YCl3 6 | YCl3 6 | YCl3 6 | YCl3 6 |
Tribromide | LaBr3 | CeBr3 | PrBr3 | NdBr3 | PmBr3 | SmBr3 | EuBr3 | GdBr3 | TbBr3 | DyBr3 | HoBr3 | ErBr3 | TmBr3 | YbBr3 | LuBr3 |
Color m.p. °C | white 783 | white 733 | green 691 | violet 682 | green 693 | yellow 640 | grey dec | white 770 | white 828 | white 879 | yellow 919 | violet 923 | white 954 | white dec | white 1025 |
Structure C.N. | UCl3 9 | UCl3 9 | UCl3 9 | PuBr3 8 | PuBr3 8 | PuBr3 8 | PuBr3 8 | 6 | 6 | 6 | 6 | 6 | 6 | 6 | 6 |
Triiodide | LaI3 | CeI3 | PrI3 | NdI3 | PmI3 | SmI3 | EuI3 | GdI3 | TbI3 | DyI3 | HoI3 | ErI3 | TmI3 | YbI3 | LuI3 |
Color m.p. °C | yellow 766 | green 738 | green 784 | green 737 | orange 850 | dec. | yellow 925 | 957 | green 978 | yellow 994 | violet 1015 | yellow 1021 | white dec | brown 1050 | |
Structure C.N. | PuBr3 8 | PuBr3 8 | PuBr3 8 | PuBr3 8 | BiI3 6 | BiI3 6 | BiI3 6 | BiI3 6 | BiI3 6 | BiI3 6 | BiI3 6 | BiI3 6 | BiI3 6 | BiI3 6 | |
Difluoride | SmF2 | EuF2 | TmF2 | YbF2 | |||||||||||
Color m.p. °C | purple 1417 | yellow 1416 | grey | ||||||||||||
Structure C.N. | CaF2 8 | CaF2 8 | CaF2 8 | ||||||||||||
Dichloride | NdCl2 | SmCl2 | EuCl2 | DyCl2 | TmCl2 | YbCl2 | |||||||||
Color m.p. °C | green 841 | brown 859 | white 731 | black dec. | green 718 | green 720 | |||||||||
Structure C.N. | PbCl2 9 | PbCl2 9 | PbCl2 9 | SrBr2 | SrI2 7 | SrI2 7 | |||||||||
Dibromide | NdBr2 | SmBr2 | EuBr2 | DyBr2 | TmBr2 | YbBr2 | |||||||||
Color m.p. °C | green 725 | brown 669 | white 731 | black | green | yellow 673 | |||||||||
Structure C.N. | PbCl2 9 | SrBr2 8 | SrBr2 8 | SrI2 7 | SrI2 7 | SrI2 7 | |||||||||
Diiodide | LaI2 metallic |
CeI2 metallic |
PrI2 metallic |
NdI2 high pressure metallic |
SmI2 | EuI2 | GdI2 metallic |
DyI2 | TmI2 | YbI2 | |||||
Color m.p. °C | bronze 808 | bronze 758 | violet 562 | green 520 | green 580 | bronze 831 | purple 721 | black 756 | yellow 780 | Lu | |||||
Structure C.N. | CuTi2 8 | CuTi2 8 | CuTi2 8 | SrBr2 8 CuTi2 8 |
EuI2 7 | EuI2 7 | 2H-MoS2 6 | CdI2 6 | CdI2 6 | ||||||
Ln7I12 | La7I12 | Pr7I12 | Tb7I12 | ||||||||||||
Sesquichloride | La2Cl3 | Gd2Cl3 | Tb2Cl3 | Er2Cl3 | Tm2Cl3 | Lu2Cl3 | |||||||||
Structure | Gd2Cl3 | Gd2Cl3 | |||||||||||||
Sesquibromide | Gd2Br3 | Tb2Br3 | |||||||||||||
Structure | Gd2Cl3 | Gd2Cl3 | |||||||||||||
Monoiodide | LaI[12] | ||||||||||||||
Structure | NiAs type |
Tetrahalides
Of the lanthanide tetrahalides, only the fluorides of cerium, praseodymium and terbium are well characterised. NdF4 and DyF4 have also been characterised.
Trihalides
Dihalides
Lower halides
Oxides
info about oxides
Monoxides
SmO EuO
Sesquioxides
All lanthanides form
Dioxides
CeO2 PrO2 TbO2
Other oxides
Pr-O Tb-O Ce-O?
Chalcogenides
Sulfides
Selenides
Tellurides
Hydroxides
basic info about hydroxides
Pnictides
Nitrides
Phosphides
Arsenides
Antimonides and bismuthides?
Carbides
maybe silicides but probably not
Borides
Diborides
Diborides, LnB2, have been reported for Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu. All have the same, AlB2, structure containing a graphitic layer of boron atoms. Low temperature ferromagnetic transitions for Tb, Dy, Ho and Er. TmB2 is ferromagnetic at 7.2 K.[8]
Tetraborides
Tetraborides, LnB4, have been reported for all of the lanthanides except EuB4, all have the same UB4 structure. The structure has a boron sub-lattice consists of chains of octahedral B6 clusters linked by boron atoms. The unit cell decreases in size successively from LaB4 to LuB4. The tetraborides of the lighter lanthanides melt with decomposition to LnB6.[13] Attempts to make EuB4 have failed.[14] The LnB4 are good conductors[15] and typically antiferromagnetic.[8]
Hexaborides
Hexaborides, LnB6, have been reported for all of the lanthanides. They all have the CaB6 structure, containing B6 clusters. They are non-stoichiometric due to cation defects. The hexaborides of the lighter lanthanides (La – Sm) melt without decomposition, EuB6 decomposes to boron and metal and the heavier lanthanides decompose to LnB4 with exception of YbB6 which decomposes forming YbB12. The stability has in part been correlated to differences in volatility between the lanthanide metals.[13] In EuB6 and YbB6 the metals have an oxidation state of +2 whereas in the rest of the lanthanide hexaborides it is +3. This rationalises the differences in conductivity, the extra electrons in the LnIII hexaborides entering conduction bands. EuB6 is a semiconductor and the rest are good conductors.[8][13] LaB6 and CeB6 are thermionic emitters, used, for example, in scanning electron microscopes.[16]
Dodecaborides
Lanthanide dodecaborides, LnB12, are formed by the heavier smaller lanthanides from Gd to Lu. With the exception YbB12 (where Yb takes an intermediate valence and is a Kondo insulator), the dodecaborides are all metallic compounds. They all have the UB12 structure containing a 3 dimensional framework of cubooctahedral B12 clusters.[15]
Higher borides
The higher boride LnB66 is known for all lanthanide metals. The composition is approximate as the compounds are non-stoichiometric.[15] They all have similar complex structure with over 1600 atoms in the unit cell. The boron cubic sub lattice contains super icosahedra made up of a central B12 icosahedra surrounded by 12 others, B12(B12)12.[15] Other complex higher borides LnB50 (Tb, Dy, Ho Er Tm Lu) and LnB25 are known (Gd, Tb, Dy, Ho, Er) and these contain boron icosahedra in the boron framework.[15]
Organolanthanide compounds
stuff
See also
References
- ^ Some page from G&E
- ^ a b Fukai, Y. (2005). The Metal-Hydrogen System, Basic Bulk Properties, 2d edition. Springer. ISBN 978-3-540-00494-3.
- ^ Kohlmann, H.; Yvon, K. (2000). "The crystal structures of EuH2 and EuLiH3 by neutron powder diffraction". Journal of Alloys and Compounds. 299 (1–2): L16–L20. doi:10.1016/S0925-8388(99)00818-X.
- ^ Matsuoka, T.; Fujihisa, H.; Hirao, N.; Ohishi, Y.; Mitsui, T.; Masuda, R.; Seto, M.; Yoda, Y.; Shimizu, K.; Machida, A.; Aoki, K. (2011). "Structural and Valence Changes of Europium Hydride Induced by Application of High-Pressure H2". Physical Review Letters. 107 (2): 025501. Bibcode:2011PhRvL.107b5501M. doi:10.1103/PhysRevLett.107.025501. PMID 21797616.
- ^ Tellefsen, M.; Kaldis, E.; Jilek, E. (1985). "The phase diagram of the Ce-H2 system and the CeH2-CeH3 solid solutions". Journal of the Less Common Metals. 110 (1–2): 107–117. doi:10.1016/0022-5088(85)90311-X.
- ^ Kumar, Pushpendra; Philip, Rosen; Mor, G. K.; Malhotra, L. K. (2002). "Influence of Palladium Overlayer on Switching Behaviour of Samarium Hydride Thin Films". Japanese Journal of Applied Physics. 41 (Part 1, No. 10): 6023–6027. Bibcode:2002JaJAP..41.6023K. doi:10.1143/JJAP.41.6023. S2CID 96881388.
- ^ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. pp. 1230–1242. ISBN 978-0-08-037941-8.
- ^ a b c d David A. Atwood, ed. (19 February 2013). The Rare Earth Elements: Fundamentals and Applications (eBook). John Wiley & Sons. ISBN 9781118632635.
- ^ Wells, A. F. (1984). Structural Inorganic Chemistry (5th ed.). Oxford Science Publication. ISBN 978-0-19-855370-0.
- ^ Holleman, p. 1942
- ^ Perry, Dale L. (2011). Handbook of Inorganic Compounds, Second Edition. Boca Raton, Florida: CRC Press. p. 125. ISBN 978-1-43981462-8. Retrieved 17 February 2014.
- ^ Ryazanov, Mikhail; Kienle, Lorenz; Simon, Arndt; Mattausch, Hansjürgen (2006). "New Synthesis Route to and Physical Properties of Lanthanum Monoiodide†". Inorganic Chemistry. 45 (5): 2068–2074. doi:10.1021/ic051834r. PMID 16499368.
- ^ a b c Cite error: The named reference
InorgReactvol13
was invoked but never defined (see the help page). - ^ Cite error: The named reference
Alper
was invoked but never defined (see the help page). - ^ a b c d e Cite error: The named reference
Mori handbookvol38
was invoked but never defined (see the help page). - ^ Reimer, Ludwig (1993). Image Formation in Low-voltage Scanning Electron Microscopy. SPIE Press. ISBN 978-0-8194-1206-5.