Supramolekulski motivi u kristalnim strukturama kadmijevih(II) kompleksa s odabranim oksimima - od strukture do elastičnih svojstava

master's thesis

• Title (english): Supramolecular motifs in crystal structures of cadmium(II) complexes with selected oxymes - from structure to elastic properties
• Author: Vedran Barbarić
• Mentor: Marijana Đaković (mentor)
• Mentor: Zlatko Mihalić (mentor)
• Committee member: Marijana Đaković (predsjednik povjerenstva)
• Committee member: Ivan Kodrin (član povjerenstva)
• Committee member: Tajana Preočanin (član povjerenstva)
• Committee member: Iva Juranović Cindrić (član povjerenstva)
• Committee member: Željka Soldin (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Chemistry); Zagreb
• Defense date and country: 2017-02-28, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry

Abstract

U sklopu ovog rada pripravljeni su spojevi kadmijevih(II) halogenida s derivatima 4-piridilaldoksima (4-piridilaldoksim; 4-Hoxpy, metil-4-piridilketoksim; 4-Meoxpy, amino-4-piridilketoksim; 4-NH2oxpy). Priređeno je devet novih kompleksnih spojeva ([CdI2(4-Hoxpy)2]n, [CdI2(4-Meoxpy)2]n, [CdI2(4-NH2oxpy)2]n, [CdBr2(4-Hoxpy)2]n, [CdBr2(4-Meoxpy)2]n, [CdBr2(4-NH2oxpy)2]n, [CdCl2(4-Hoxpy)2]n, [CdCl2(4-Meoxpy)2]n, [CdCl2(4-NH2oxpy)2]n) klasičnom otopinskom i mehanokemijskom sintezom. Svi spojevi okarakterizirani su spektroskopskim (IR) i termičkim metodama (TG i DSC) te difrakcijom rendgenskih zraka u polikristalnom uzorku. Za pet spojeva određena je molekulska i kristalna struktura rendgenskom strukturnom analizom.
Kako bi se objasnilo povezivanje susjednih molekula uz ostvarivanje određenih supramolekulskih motiva u kristalnoj strukturi za svaki spoj izračunate su vrijednosti elektrostatskog potencijala za potencijalne donore i akceptore u vodikovim vezama. Korištena je DFT metoda pri čemu su koordinacijski polimeri modelirani pomoću periodičnih graničnih uvjeta. Nova, predložena metoda računanja mapa elektrostatskog potencijala ispitana je na sintetiziranim spojevima te može pomoći pri predviđanju nastajanja najvjerojatnijih supramolekulskih sintona. Ispitana su mehanička svojstva dobivenih kristala pri čemu se pokazalo kako [CdBr2(4-Hoxpy)2]n pokazuje elastična svojstva.

Abstract (english)

Within this thesis nine complexes of cadmium(II) with halide and 4-pyridylaldoxime derivatives (4-pyridylaldoxime; 4-Hoxpy, methyl-4-pyridylketoxime; 4-Meoxpy, amino-4-pyridylketoxime; 4-NH2oxpy) were prepared. The complexes ([CdI2(4-Hoxpy)2]n, [CdI2(4-Meoxpy)2]n, [CdI2(4-NH2oxpy)2]n, [CdBr2(4-Hoxpy)2]n, [CdBr2(4-Meoxpy)2]n, [CdBr2(4-NH2oxpy)2]n, [CdCl2(4-Hoxpy)2]n, [CdCl2(4-Meoxpy)2]n, [CdCl2(4-NH2oxpy)2]n) were prepared by classical solution as well as mechanochemical synthesis. The complexes were characterized by means of spectroscopic (IR) and thermal methods (TG/DTA) as well as by diffraction of X-rays on polycrystalline samples. For five complexes molecular and crystal structure were determined by diffraction of X-rays on single crystals.
To provide an explanation on how the neighbouring molecules mutually link via particular supramolecular motifs in the crystal structure, molecular electrostatic potentials (on potential hydrogen bond donor and acceptor sites) were calculated by means of DFT studies on coordination polymers modelled with periodic boundary conditions. A new procedure for calculations of molecular electrostatic potential maps was developed and tested on the synthetized compounds. It can be used as a complementary prediction tool to estimate the most probable supramolecular synthons. Mechanical properties of the obtained crystals were assessed and only [CdBr2(4-Hoxpy)2]n was found as a good candidate for elastically bending.

• Keywords: elektrostatski potencijali; kadmij; koordinacijski polimer; kristalna struktura; molekularno modeliranje; oksimi; vodikove veze; elastični kristali
• Keywords (english): cadmium; coordination polymers; crystal structure; electrostatic potential; hydrogen bonds; molecular modelling; oximes; elastic properties of crystals
• Language: croatian
• URN:NBN: urn:nbn:hr:217:355468
• Study programme: Title: Graduate university studies in chemistry; specializations in: Research programme; Course: Research programme; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra kemije (magistar/magistra kemije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access; Embargo expiration date: 2019-03-01
• Created on: 2017-03-10 12:07:20