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Intermolecular interactions in compressed crystals
Damian Paliwoda
Abstract
Pressure is an effective tool for tuning crystal structure by changing energetical hierarchy of non-bonding forces. Pressure can induce phase transitions and structural changes, leading to new molecular arrangements, of varied physical properties, such as crystal polarity and optical properties. Three examples of pressure-induced transformations of molecular crystals have been presented in my thesis. High-pressure recrystallization of imidazole has led to its new polymorph, where the infinite NH•••N bonded chains of molecules assume polar arrangement. The lengths of NH•••N bonds are shorter in the high pressure polymorph, which facilitates proton hopping in a double-well potential. The conformation of metallocene molecules has been intensively investigated due to the very low energy barrier between staggered and eclipsed forms. It was postulated previously that at ambient conditions cyclopentadienyl rings in ferrocene are dynamically disordered in two sites. These disorder is eliminated at high pressure leading to unexpected anomalous evolution of lattice parameters with pressure. Aurophilic interaction is a very unusual type of intermetallic bonds, in which relativistic effects play a substantial role. So far studies on the high-pressure evolution of Au•••Au distances are very limited and this work reports the first compressibility measurements of this effect. It was shown in this thesis that pressure can partly unwind helical Au•••Au bonded filaments.- Record ID
- UAM1393aafede8b426dac9ccff99356e8b2
- Diploma type
- Doctor of Philosophy
- Author
- Title in Polish
- Oddziaływania międzycząsteczkowe w kryształach pod wysokim ciśnieniem
- Title in English
- Intermolecular interactions in compressed crystals
- Language
- (en) English
- Certifying Unit
- Wydział Chemii [nowa struktura organizacyjna] (SNŚ/WC)
- Scientific discipline (2.0)
- Status
- Finished
- Year of creation
- 2014
- Defense Date
- 27-03-2014
- Title date
- 27-03-2014
- Supervisor
- URL
- https://hdl.handle.net/10593/10361 Opening in a new tab
- Keywords in English
- high pressure,compressibility,high-pressure Crystallography,intermolecular interactions
- Abstract in English
- Pressure is an effective tool for tuning crystal structure by changing energetical hierarchy of non-bonding forces. Pressure can induce phase transitions and structural changes, leading to new molecular arrangements, of varied physical properties, such as crystal polarity and optical properties. Three examples of pressure-induced transformations of molecular crystals have been presented in my thesis. High-pressure recrystallization of imidazole has led to its new polymorph, where the infinite NH•••N bonded chains of molecules assume polar arrangement. The lengths of NH•••N bonds are shorter in the high pressure polymorph, which facilitates proton hopping in a double-well potential. The conformation of metallocene molecules has been intensively investigated due to the very low energy barrier between staggered and eclipsed forms. It was postulated previously that at ambient conditions cyclopentadienyl rings in ferrocene are dynamically disordered in two sites. These disorder is eliminated at high pressure leading to unexpected anomalous evolution of lattice parameters with pressure. Aurophilic interaction is a very unusual type of intermetallic bonds, in which relativistic effects play a substantial role. So far studies on the high-pressure evolution of Au•••Au distances are very limited and this work reports the first compressibility measurements of this effect. It was shown in this thesis that pressure can partly unwind helical Au•••Au bonded filaments.
- Thesis file
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- File: 1
- PhDthesis_DPaliwoda.pdf
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- Uniform Resource Identifier
- https://researchportal.amu.edu.pl/info/phd/UAM1393aafede8b426dac9ccff99356e8b2/
- URN
urn:amu-prod:UAM1393aafede8b426dac9ccff99356e8b2