Mechanochemical synthesis and structural characterization of bimetallic and hybrid tetrahydridoborates

doctoral thesis

• Title (croatian): Mehanokemijska sinteza i strukturna karakterizacija dimetalnih i hibridnih tetrahidridoborata
• Author: Sanja Burazer
• Mentor: Jasminka Popović (mentor)
• Committee member: Vladimir Stilinović (predsjednik povjerenstva)
• Committee member: Marijana Jurić (član povjerenstva)
• Committee member: Dubravka Matković-Čalogović (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Chemistry); Zagreb
• Defense date and country: 2019-10-18, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry
• Universal decimal classification (UDC): 54 - Chemistry. Crystallography. Mineralogy

Abstract

Mechanochemical reactions of metal tetrahydridoborates and metal imidazolates, as well as the structural characteristics of the obtained products were investigated. X-ray powder diffraction, both at the laboratory diffractometer and in-situ high-temperature diffraction under the synchrotron radiation was mainly used experimental technique. NMR was used as a complementary technique. Combination of molecular building blocks of lithium borohydride, LiBH4, and lithium imidazolate, LiIm, led to the formation of hybrid Li2ImBH4 with a high conversion rate. New compounds containing alkali and alkaline earth metal centers, AMgIm3 (A = Na, K), were found. New compounds of manganese imidazolates with alkaline metal centers were prepared, AMnIm3 (A = Na, K). Crystal structure determination of the new compounds was carried out from the powder diffraction data using methods in the direct space. New methods of preparation of crystalline magnesium imidazolate, MgIm2, and high-temperature polymorph of sodium imidazolate, HT-NaIm, are described. Structure of HT-NaIm was determined from the single crystal diffraction data.

Abstract (croatian)

Istražene su mehanokemijske reakcije metalnih tetrahidridoborata i metalnih imidazolata te strukturne značajke dobivenih produkata. Rendgenska difrakcija u polikristalu na laboratorijskom difraktometru te in-situ visokotemperaturna difrakcija na sinkrotronskoj liniji najvažnije su eksperimentalne tehnike korištene u ovom radu, a neki uzorci dodatno su okarakterizirani pomoću nuklearne magnetske rezonancije u čvrstom stanju. Poboljšan je sintetski put priprave hibridne metalohidridne organske mreže, Li2ImBH4, nastale kombinacijom molekulskih građevnih blokova litijevog borohidrida, LiBH4, i litijevog imidazolata, LiIm, uz visok stupanj konverzije. Otkrivena je nova skupina dimetalnih magnezijevih imidazolata, prvih imidazolatnih spojeva koji sadrže alkalijske i zemnoalkalijske metalne centre, AMgIm3 (A = Na, K). Priređeni su novi dimetalni spojevi manganovog imidazolata s alkalijskim metalnim centrima, AMnIm3 (A = Na, K). Određivanje struktura novih spojeva provedeno je iz difrakcijskh podataka polikristalnih uzoraka pomoću metoda u direktnom prostoru. Otkriven je nov način pripreme kristalnog magnezijevog imidazolata, MgIm2, te visokotemperaturnog (HT) polimorfa natrijevog imidazolata, HT-NaIm, čija struktura je određena iz difrakcijskih podataka jediničnog kristala

• Keywords: mechanochemical synthesis; tetrahydridoborates; hybrid metal-organic frameworks; imidazolate; X-ray powder diffraction; synchrotron radiation; crystal structure determination
• Keywords (croatian): mehanokemijska sinteza; tetrahidridoborati; hibridne metaloorganske mreže; imidazolati; rendgenska difrakcija u polikristalu; sinkrotron; određivanje kristalne strukture
• Language: english
• URN:NBN: urn:nbn:hr:217:131290
• Study programme: Title: Doctoral study in chemistry; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti, područje prirodnih znanosti, polje kemija (doktor/doktorica znanosti, područje prirodnih znanosti, polje kemija)
• Type of resource: Text
• Extent: 163 str. ; 30 cm
• File origin: Born digital
• Access conditions: Open access; Embargo expiration date: 2021-04-19
• Created on: 2019-12-04 14:20:31