Details

Autor(en) / Beteiligte

• Shmakova, Alexandra A
• Akhmetova, Maria M
• Volchek, Victoria V
• Romanova, Tamara E
• Korolkov, Ilya
• Sheven, Dmitri G
• Adonin, Sergey A
• Abramov, Pavel A
• Sokolov, Maxim N

Titel

A HPLC-ICP-AES technique for the screening of [XW11NbO40]n− aqueous solutionsElectronic supplementary information (ESI) available: HPLC-ICP-AES, XRD, XRPD details. CCDC 1587891 and 1587892. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c7nj04702a

Erscheinungsjahr

2018-05

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• The reaction of H 3 [PW 12 O 40 ] with (NH 4 )[NbO(C 2 O 4 ) 2 (H 2 O) 2 ]·3H 2 O leads to the straightforward incorporation of Nb into a Keggin anion backbone resulting in [PW 11 NbO 40 ] 4− in nearly quantitative yield. Solution behavior of this monosubstituted anion as a function of pH was studied through 31 P NMR and HPLC-ICP-AES techniques (a combination of chromatography and ICP-AES). Increasing of the pH leads to the elimination of Nb from the structure with the formation of mixed Nb/W Lindqvist-type anions and monolacunary [PW 11 O 39 ] 7− . In aged solutions of [PW 11 NbO 40 ] 4− the formation of a mixture of [PNb 2 W 10 O 39 ] 5− isomers was detected. The HPLC-ICP-AES technique was applied for the study of [BW 11 O 39 ] 9− behavior in aqueous solutions at different pH values and for monitoring the [GeW 11 O 39 ] 4− reaction with the niobium oxalate complex. Despite the presence of the nucleophilic Nb&z.dbd;O group [PW 11 NbO 40 ] 4− does not coordinate Co 2+ in DMF or Ni 2+ in CH 3 CN, producing double [Co(DMF) 6 ][PW 11 NbO 40 ]·2.6DMF ( 2 ) and [Ni(CH 3 CN) 5.5 (H 2 O) 0.5 ] 2 [PW 11 NbO 40 ]·1.7CH 3 CN ( 3 ) salts instead. In this research combined HPLC-ICP-AES technique was used to study formation of mixed [XW 11 O 40 ] n − (X = P, Ge, B) complexes.