New calcium germanium nitrides: Ca2GeN2, Ca4GeN4, and Ca5Ge2N6.
We report three new calcium germanium nitrides synthesized as crystals from the elements in sealed niobium tubes at 760 degrees C using liquid sodium as a growth medium. Black Ca2GeN2 is isostructural with the previously reported strontium analogue. It is tetragonal P4(2)/mbc (no. 135) with a = 11.2...
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| Format: | Journal article |
| Language: | English |
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2000
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| _version_ | 1797081566794481664 |
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| author | Clarke, S DiSalvo, F |
| author_facet | Clarke, S DiSalvo, F |
| author_sort | Clarke, S |
| collection | OXFORD |
| description | We report three new calcium germanium nitrides synthesized as crystals from the elements in sealed niobium tubes at 760 degrees C using liquid sodium as a growth medium. Black Ca2GeN2 is isostructural with the previously reported strontium analogue. It is tetragonal P4(2)/mbc (no. 135) with a = 11.2004(8) A, c = 5.0482(6) A, and Z = 8. It contains GeN2(4-) units which have 18 valence electrons, and consequently are bent, like the isoelectronic molecule SO2. In contrast, clear, orange Ca4GeN4 with fully oxidized germanium contains isolated GeN4(8-) tetrahedra and is monoclinic P2(1)/c (no. 14) with a = 9.2823(8) A, b = 6.0429(5) A, c = 11.1612(9) A, beta = 116.498(6) degrees, and Z = 4. Clear, colorless Ca5Ge2N6, also with fully oxidized germanium, contains infinite chains, 1 infinity[GeN2N2/2(5-)], of corner-sharing tetrahedra similar to those found in pyroxenes. However, the precise structure of this latter phase has not yet been determined because of twinning problems. |
| first_indexed | 2024-03-07T01:16:04Z |
| format | Journal article |
| id | oxford-uuid:8eb855ee-4691-4ffb-876f-4ae5b190f71d |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-07T01:16:04Z |
| publishDate | 2000 |
| record_format | dspace |
| spelling | oxford-uuid:8eb855ee-4691-4ffb-876f-4ae5b190f71d2022-03-26T22:59:34ZNew calcium germanium nitrides: Ca2GeN2, Ca4GeN4, and Ca5Ge2N6.Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:8eb855ee-4691-4ffb-876f-4ae5b190f71dEnglishSymplectic Elements at Oxford2000Clarke, SDiSalvo, FWe report three new calcium germanium nitrides synthesized as crystals from the elements in sealed niobium tubes at 760 degrees C using liquid sodium as a growth medium. Black Ca2GeN2 is isostructural with the previously reported strontium analogue. It is tetragonal P4(2)/mbc (no. 135) with a = 11.2004(8) A, c = 5.0482(6) A, and Z = 8. It contains GeN2(4-) units which have 18 valence electrons, and consequently are bent, like the isoelectronic molecule SO2. In contrast, clear, orange Ca4GeN4 with fully oxidized germanium contains isolated GeN4(8-) tetrahedra and is monoclinic P2(1)/c (no. 14) with a = 9.2823(8) A, b = 6.0429(5) A, c = 11.1612(9) A, beta = 116.498(6) degrees, and Z = 4. Clear, colorless Ca5Ge2N6, also with fully oxidized germanium, contains infinite chains, 1 infinity[GeN2N2/2(5-)], of corner-sharing tetrahedra similar to those found in pyroxenes. However, the precise structure of this latter phase has not yet been determined because of twinning problems. |
| spellingShingle | Clarke, S DiSalvo, F New calcium germanium nitrides: Ca2GeN2, Ca4GeN4, and Ca5Ge2N6. |
| title | New calcium germanium nitrides: Ca2GeN2, Ca4GeN4, and Ca5Ge2N6. |
| title_full | New calcium germanium nitrides: Ca2GeN2, Ca4GeN4, and Ca5Ge2N6. |
| title_fullStr | New calcium germanium nitrides: Ca2GeN2, Ca4GeN4, and Ca5Ge2N6. |
| title_full_unstemmed | New calcium germanium nitrides: Ca2GeN2, Ca4GeN4, and Ca5Ge2N6. |
| title_short | New calcium germanium nitrides: Ca2GeN2, Ca4GeN4, and Ca5Ge2N6. |
| title_sort | new calcium germanium nitrides ca2gen2 ca4gen4 and ca5ge2n6 |
| work_keys_str_mv | AT clarkes newcalciumgermaniumnitridesca2gen2ca4gen4andca5ge2n6 AT disalvof newcalciumgermaniumnitridesca2gen2ca4gen4andca5ge2n6 |