Managing Hydrogen Bonding in the Clathrate Hydrate of the 1-Pentanol Guest Molecule

CrystEngComm ◽  
2021 ◽  
Author(s):  
Byeonggwan Lee ◽  
Jeongtak Kim ◽  
Kyuchul Shin ◽  
Ki Hun Park ◽  
Minjun Cha ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Guest Molecule ◽  
Clathrate Hydrate ◽  
Guest Molecules

It remains a difficult task to predict the hydrate structure and conformation of potential guest molecules in one of the three canonical hydrate lattices. 1-pentanol is characteristic of molecules that...

Structural Transition of Trimethylamine Hydrate by Methane or Hydrogen Inclusion

2020 ◽  
Author(s):  
Minjun Cha
Keyword(s):  
Structural Transition ◽  
Guest Molecule ◽  
Clathrate Hydrate ◽  
Hydrogen Gas ◽  
Time Dependent ◽  
X Ray Diffraction ◽  
Guest Molecules ◽  
X Ray ◽  
Inclusion Process ◽  
Diffraction Patterns

<p>Recently, several alkylamine hydrates have been studied in an effort to reveal the structural transitions from semi- to ‘canonical’ clathrate hydrate in the presence of secondary guest molecules. Trimethylamine (TMA) is known to form the semi-clathrate hydrate, and it has been reported that the structural transition of the TMA semi-clathrate hydrate may not occur in the presence of hydrogen gas as a secondary guest molecule. This paper reports the structural transition of trimethylamine(TMA) hydrate induced by the type of guest molecules. Powder X-ray diffraction patterns of (TMA + H<sub>2</sub>) hydrates show the formation of hexagoanl P6/mmm hydrate, but those of (TMA + CH<sub>4</sub>) hydrates indicate the formation of cubic Fd3m hydrate. Without gaseous guest molecule, the crystal structure of pure TMA hydrate is identified as hexagonal P6/mmm. Therefore, inclusion of gaseous methane in TMA hydrate can induce the structural transition from hexagonal to cubic hydrate or the formation of metastable cubic hydrate. To clearly reveal this possibility, we also check the time-dependent structural patterns of binary (TMA + CH<sub>4</sub>) hydrates from 1 to 14 days, and the results show that the structural transition of TMA hydrate from hexagonal P6/mmm to cubic Fd3m hydrate structure can occur during the methane inclusion process.</p>

Modeling Dissociation Pressure of Semi-Clathrate Hydrate Systems Containing CO2, CH4, N2, and H2S in the Presence of Tetra-n-butyl Ammonium Bromide

2019 ◽  
Vol 44 (1) ◽  
pp. 15-28 ◽  
Author(s):  
Mohammad Mesbah ◽  
Ebrahim Soroush ◽  
Mashallah Rezakazemi
Keyword(s):  
Gas Phase ◽  
Mass Fraction ◽  
Guest Molecule ◽  
Clathrate Hydrate ◽  
Clathrate Hydrates ◽  
Ammonium Bromide ◽  
Guest Molecules ◽  
Dissociation Pressure ◽  
Tuning Parameters ◽  
Langmuir Adsorption

Abstract In this study, the phase equilibria of semi-clathrate hydrates of methane (CH4), carbon dioxide (CO2), nitrogen (N2), and hydrogen sulfide (H2S) in an aqueous solution of tetra-n-butyl ammonium bromide (TBAB) were modeled using a correlation based on a two-stage formation mechanism: a quasi-chemical reaction that forms basic semi-clathrate hydrates and adsorption of guest molecules in the linked cavities of the basic semi-clathrate hydrate. The adsorption of guest molecules was described by the Langmuir adsorption theory and the fugacity of the gas phase was calculated by Peng–Robinson (PR) equation of state (EOS). The water activity in the presence of TBAB was calculated using a correlation, dependent on temperature, the TBAB mass fraction, and the nature of the guest molecule. These equations were coupled together and form a correlation which was linked to a genetic algorithm for optimization of tuning parameters. The results showed an excellent agreement between model results and experimental data. In addition, an outlier diagnostic was performed for finding any possible doubtful data and assessing the applicability of the model. The results showed that more than 97 % of the data were reliable and they were in the applicability domain of the model.

scholarly journals Formation of quinol co-crystals with hydrogen-bond acceptors

2005 ◽  
Vol 61 (1) ◽  
pp. 46-57 ◽  
Author(s):  
Iain D. H. Oswald ◽  
W. D. Samuel Motherwell ◽  
Simon Parsons
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Crystal Structures ◽  
Guest Molecule ◽  
Crystal Packing ◽  
Strong Hydrogen Bond ◽  
Hydrogen Bond Acceptor ◽  
Guest Molecules ◽  
Sterically Hindered

The crystal structures of eight new co-crystals of quinol with pyrazine, piperazine, morpholine, pyridine, piperidine, 4,4′-bipyridine, N-methylmorpholine and N,N′-dimethylpiperazine are reported. Quinol forms 1:1 co-crystals with pyrazine, piperazine and N,N′-dimethylpiperazine, but 1:2 co-crystals with morpholine, 4,4′-bipyridine, N-methylmorpholine, pyridine and piperidine. This difference can be rationalized in most cases by the presence of, respectively, two or one strong hydrogen-bond acceptor(s) in the guest molecule. The exception to this generalization is 4,4′-bipyridine, which forms a 1:2 co-crystal, possibly to optimize crystal packing. All structures are dominated by hydrogen bonding between quinol and the guest molecules. A doubly bridging motif, which connects pairs of quinol and guest molecules via NH...O or CH...O interactions, is present in all but the sterically hindered N,N′-dimethylpiperazine and N-methylmorpholine co-crystals.

scholarly journals Hydrogen Inter-Cage Hopping and Cage Occupancies inside Hydrogen Hydrate: Molecular-Dynamics Analysis

2020 ◽  
Vol 11 (1) ◽  
pp. 282
Author(s):  
Yogeshwaran Krishnan ◽  
Mohammad Reza Ghaani ◽  
Arnaud Desmedt ◽  
Niall J. English
Keyword(s):  
Molecular Dynamics ◽  
Energy Barrier ◽  
Guest Molecule ◽  
Arrhenius Equation ◽  
Dynamics Simulation ◽  
Type Ii ◽  
Large Cage ◽  
Guest Molecules ◽  
Simulation Time ◽  
Average Occupancy

The inter-cage hopping in a type II clathrate hydrate with different numbers of H2 and D2 molecules, from 1 to 4 molecules per large cage, was studied using a classical molecular dynamics simulation at temperatures of 80 to 240 K. We present the results for the diffusion of these guest molecules (H2 or D2) at all of the different occupations and temperatures, and we also calculated the activation energy as the energy barrier for the diffusion using the Arrhenius equation. The average occupancy number over the simulation time showed that the structures with double and triple large-cage H2 occupancy appeared to be the most stable, while the small cages remained with only one guest molecule. A Markov model was also calculated based on the number of transitions between the different cage types.

Hydrogen-bonding networks of purine derivatives and their bilayers for guest intercalation

CrystEngComm ◽  
2016 ◽  
Vol 18 (1) ◽  
pp. 62-67
Author(s):  
Yoona Jang ◽  
Seo Yeon Yoo ◽  
Hye Rin Gu ◽  
Yu Jin Lee ◽  
Young Shin Cha ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Two Dimensional ◽  
Purine Derivatives ◽  
Guest Molecules ◽  
Π Interactions ◽  
Hydrogen Bonding Networks ◽  
Hydrogen Bonded

6-Chloro-9-propyl-purin-2-amine (pr-GCl) forms two-dimensional hydrogen-bonded networks which in turn stack via π–π interactions, leading to the formation of bilayers that can accommodate organic guest molecules.

Clathrate and other solid phases in the tetrahydrofuran–water system: thermal conductivity and heat capacity under pressure

1982 ◽  
Vol 60 (7) ◽  
pp. 881-892 ◽  
Author(s):  
Russell G. Ross ◽  
Per Andersson
Keyword(s):  
Thermal Conductivity ◽  
Heat Capacity ◽  
Water System ◽  
Clathrate Hydrate ◽  
Transient Hot Wire ◽  
Guest Molecules ◽  
Hydrate Phase ◽  
Wire Method ◽  
Solid Phases ◽  
Thermal Conductivity Λ

Solid phases in the tetrahydrofuran–water (THF–H2O) system were investigated in the temperature range 100–260 K and at pressures up to 1.5 GPa. Thermal conductivity, λ, and heat capacity per unit volume, ρcp, were measured, using the transient hot-wire method. We made measurements on solid phases having nominal compositions THF•17H2O, THF•7•1H2O, and THF•4•6H2O, which we refer to as phases α, β, and γ, respectively. Phase α is known to be a structure II clathrate hydrate, and λ for this phase was found to be similar to other crystalline solids which are glass-like in relation to their thermal properties. Low-energy excitations are known to be relevant to the properties of glass-like solids, and, in the case of phase α, were probably rotational vibrations of the THF guest molecules. Phase β was similar, and we inferred that it was probably a structure I clathrate hydrate. Phase γ behaved nearly like a normal crystal phase at low temperatures, but λ became almost independent of temperature near melting. At 1.1 GPa and 130 K, we found evidence that phase α transformed, on pressurization, to a metastable modification which may be a new high-density form of clathrate hydrate. The astrophysical implications of our results were mentioned briefly.

scholarly journals Effects of the CO2 Guest Molecule on the sI Clathrate Hydrate Structure

Materials ◽  
2016 ◽  
Vol 9 (9) ◽  
pp. 777 ◽  
Author(s):  
Fernando Izquierdo-Ruiz ◽  
Alberto Otero-de-la-Roza ◽  
Julia Contreras-García ◽  
Olga Prieto-Ballesteros ◽  
Jose Recio
Keyword(s):  
Guest Molecule ◽  
Clathrate Hydrate

Inclusion compounds of plant growth regulators in cyclodextrins. V. 4-Chlorophenoxyacetic acid encapsulated in β-cyclodextrin and heptakis(2,3,6-tri-O-methyl)-β-cyclodextrin

2005 ◽  
Vol 61 (2) ◽  
pp. 207-217 ◽  
Author(s):  
Frantzeska Tsorteki ◽  
Kostas Bethanis ◽  
Nikos Pinotsis ◽  
Petros Giastas ◽  
Dimitris Mentzafos
Keyword(s):  
Guest Molecule ◽  
Crystal Packing ◽  
Host Molecule ◽  
X Ray Diffraction ◽  
Guest Molecules ◽  
Space Group ◽  
X Ray ◽  
Dimeric Complexes ◽  
The Mean ◽  
Chlorophenoxyacetic Acid

The crystal structures of 4-chlorophenoxyacetic acid (4CPA) included in β-cyclodextrin (β-CD) and heptakis(2,3,6-tri-O-methyl)-β-cyclodextrin (TMβCD) have been studied by X-ray diffraction. The 4CPA/β-CD complex crystallizes as a head-to-head dimer in the space group C2 in the Tetrad packing mode. The packing modes of some β-CD dimeric complexes, having unique stackings, are also discussed. The 4CPA/TMβCD inclusion complex crystallizes in the space group P21 and its asymmetric unit contains two crystallographically independent complexes, complex A and complex B, exhibiting different conformations. The host molecule of complex A is significantly distorted, as a glucosidic residue rotated about the O4′—C1 and C4—O4 bonds forms an aperture where the guest molecule is accommodated. The phenyl moiety of the guest molecule of complex B is nearly perpendicular to the mean plane of the O4n atoms. The conformations of the guest molecules of the two complexes are similar. The crystal packing consists of antiparallel columns as in the majority of the TMβCD complexes published so far.

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