Periodic Table |
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Lewis Acid/Base Interaction Matrix Database
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s-LUMO Lewis Acids

Group I & II Metal Cations | ![]() Search for s-Lewis acid species in The Chemical Thesaurus |
FMO Topology: |
The s-Lewis acids are the cations of the Group I alkali and Group II alkaline earth metals. The shell-like LUMO (2s, 3s 4s 5s & 6s AOs) is superimposed upon a sphere of closed electron shells which defines the ionic radius of the cation. |
Charge: | Positive |
HSAB: | Intrinsically hard. Fajan's rules indicate that small highly charged cations, for example Be2+, are able to polarise anions and give polar covalent complexes. |
Chemistry: | Used as counter ions or spectator ions to interesting Lewis bases. Very important biochemical species. |
Congeneric Series: |
There are two s-LUMO series: Group I alkali
metals: Li+ Na+ K+ Rb+ Cs+ |
s-LUMO Lewis acid (generic)![]() |
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Barium ion more here |
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Beryllium ion more here |
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Calcium ion more here |
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Cesium cation more here |
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Lithium ion more here |
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Magnesium ion more here |
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Potassium ion more here |
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Rubidium cation more here |
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Sodium ion more here |
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Strontium ion more here |
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Poster | Nucleophiles & Bases |
© Mark R. Leach 1999 –
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