Korelacija reverzibilnih strukturnih pretvorbi i (fero)električnih svojstava u metaloorganskim sustavima

doctoral thesis

• Title (english): Correlation of reversible structural transformations and (ferro)electric properties in metal-organic systems
• Author: Marko Dunatov
• Mentor: Lidija Androš Dubraja (mentor)
• Committee member: Jana Pisk (predsjednik povjerenstva)
• Committee member: Marijana Jurić (član povjerenstva)
• Committee member: Martina Vrankić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Chemistry); Zagreb
• Defense date and country: 2024-09-24, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry
• Universal decimal classification (UDC): 54 - Chemistry. Crystallography. Mineralogy

Abstract

Reakcijama kompleksnih aniona bis(oksalato)kroma(III), (L-tartarato)kroma(III), (L-tartarato)vanadija(IV) i (L-tartarato)vanadija(V) s odabranim kationima iz skupine 1-azabiciklo[2.2.2]oktana i 1,2-diazabiciklo[2.2.2]oktana te tetraetilamonijevim, amonijevim ili kationima natrija pripravljeno je devet sustava kompleksnih soli. Zahvaljujući fleksibilnoj strukturi reguliranoj uglavnom nekovalentnim interakcijama, priređeni spojevi prolaze kroz reverzibilne strukturne pretvorbe u čvrstom stanju potaknute promjenom različitih uvjeta (npr. temperatura, tlak) ili primjenom određenih stimulansa (npr. vanjsko električno polje, svjetlost, izloženost određenim molekulama u plinovitoj fazi). Izolirano je ukupno 20 novih spojeva. U karakterizaciji priređenih metaloorganskih spojeva korištene su infracrvena i UV/Vis-spektroskopija, TG/DTA-analiza, DSC-analiza, kao i rendgenska strukturna analiza u jediničnim kristalima i praškastim uzorcima. Strukturne pretvorbe u proučavanim sustavima, značajno utječu na spektroskopska, termička, optička (fotokromizam) odnosno električna (dielektrična, termoelektrična, feroelektrična) svojstva.

Abstract (english)

Chemical reactions of bis(oxalato)chromium(III), (L-tartrato)chromium(III), (L-tartrato)vanadium(IV) and (L-tartrato)vanadium(V) complex anions with selected cations from the 1-azabicyclo[2.2.2]octane and 1,2-diazabicyclo[2.2.2]octane family as well as tetraethylammonium, ammonium or sodium cations led to the preparation of nine complex salt systems. Due to the flexible structure, which is primarily determined by non-covalent interactions, the compounds produced undergo reversible structural transformations in the solid state when exposed to different conditions (temperature, pressure) or specific stimuli (external electric field, light, exposure to certain gas-phase molecules). A total of 20 new compounds were isolated. The metal-organic compounds produced were characterized in detail by infrared and UV/Vis spectroscopy, TG/DTA analysis, DSC analysis and X-ray structural analysis of single crystals and powder samples. The structural transformations in the investigated systems significantly influence their spectroscopic, thermal, optical (photochromism) and electrical (dielectric, thermoelectric, ferroelectric) properties.

• Keywords: dielektrici; električna svojstva; feroelektrici; metaloorganski sustavi; protonski vodiči; strukturne pretvorbe
• Keywords (english): dielectrics; electrical properties; ferroelectrics; metal-organic systems; proton conductors; structural transformations
• Language: croatian
• URN:NBN: urn:nbn:hr:217:648347
• Promotion: 2024
• Project: Number: UIP-2019-04-7433; Title: Metal-organski molekulski materijali kao potencijalni feroelektrici; Title: Metal-organic molecule-based materials as potential ferroelectrics; Acronym: MOLFERR; Leader: Lidija Androš Dubraja; Jurisdiction: Croatia; Funder: Hrvatska zaklada za znanost; Funding stream: Installation Research Projects
• Study programme: Title: Doctoral study; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica u području prirodnih znanosti (doktor/doktorica u području prirodnih znanosti)
• Type of resource: Text
• Extent: 145 str. ; 30 cm
• File origin: Born digital
• Access conditions: Open access
• Created on: 2024-10-03 13:35:23