Effect of counter ions on the mesogenic ionic N-phenylpyridiniums

CrystEngComm ◽  
2018 ◽  
Vol 20 (18) ◽  
pp. 2593-2607 ◽  
Author(s):  
Ren-Tzong Wang ◽  
Gene-Hsiang Lee ◽  
Chung K. Lai
Keyword(s):  
Ionic Liquid ◽  
Liquid Crystals ◽  
Counter Ions ◽  
Ionic Liquid Crystals ◽  
Mesomorphic Properties

Two series of ionic liquid crystals (ILCs) derived from N-phenylpyridinium 1–2 were prepared and their mesomorphic properties were investigated.

Photoresponsive ionic liquid crystals based on azobenzene guanidinium salts

2015 ◽  
Vol 17 (13) ◽  
pp. 8382-8392 ◽  
Author(s):  
Eugen Wuckert ◽  
Marc D. Harjung ◽  
Nadia Kapernaum ◽  
Carsten Mueller ◽  
Wolfgang Frey ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Liquid Crystals ◽  
Ionic Liquid Crystals ◽  
Kinetics Of ◽  
Mesomorphic Properties ◽  
Guanidinium Salts

The mesomorphic properties and the kinetics of the E/Z-photoisomerization in an ILC matrix of new azobenzene ILCs were investigated.

scholarly journals NMR Spectroscopic Study of Orientational Order in Imidazolium-Based Ionic Liquid Crystals

Crystals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 495 ◽  
Author(s):  
Jing Dai ◽  
Debashis Majhi ◽  
Boris B. Kharkov ◽  
Sergey V. Dvinskikh
Keyword(s):  
Ionic Liquid ◽  
Liquid Crystals ◽  
Structural Model ◽  
Orientational Order ◽  
Smectic Layer ◽  
Charge Delocalization ◽  
Smectic A ◽  
Counter Ions ◽  
Bonding Properties ◽  
Ionic Liquid Crystals

We report on molecular and local orientational order of a series of imidazolium-based ionic liquid crystals exhibiting layered smectic A mesophase. Materials constituting of 1-dodecyl-3-methylimidazolium cation, and different counter-ions, were investigated. We apply two-dimensional 13C-1H dipolar NMR spectroscopy to quantify orientational order of C-H bonds of the organic cation. The experimental data supported the structural model of the interdigitated chains aligned with the smectic layer normal. Molecular order parameter S was found to increase in the anion sequence BF4− < I− < Br− < Cl−. This trend correlates well with ionic radius, negative charge delocalization, and hydrogen-bonding properties of the anions.

Methimazolium-based ionic liquid crystals: Emergence of mesomorphic properties via a sulfur motif

Tetrahedron ◽  
2017 ◽  
Vol 73 (36) ◽  
pp. 5456-5460 ◽  
Author(s):  
Stephen T. Nestor ◽  
Benoît Heinrich ◽  
Richard A. Sykora ◽  
Xiaofei Zhang ◽  
Gregory J. McManus ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Liquid Crystals ◽  
Ionic Liquid Crystals ◽  
Mesomorphic Properties

scholarly journals Synthesis of guanidinium–sulfonimide ion pairs: towards novel ionic liquid crystals

2013 ◽  
Vol 9 ◽  
pp. 1093-1101 ◽  
Author(s):  
Martin Butschies ◽  
Manuel M Neidhardt ◽  
Markus Mansueto ◽  
Sabine Laschat ◽  
Stefan Tussetschläger
Keyword(s):  
Ionic Liquid ◽  
Liquid Crystals ◽  
Ion Pairs ◽  
Mesogenic Unit ◽  
Ionic Liquid Crystals ◽  
Preliminary Study ◽  
Mesomorphic Properties

The recently introduced concept of ionic liquid crystals (ILCs) with complementary ion pairs, consisting of both, mesogenic cation and anion, was extended from guanidinium sulfonates to guanidinium sulfonimides. In this preliminary study, the synthesis and mesomorphic properties of selected derivatives were described, which provide the first example of an ILC with the sulfonimide anion directly attached to the mesogenic unit.

Microwave-Assisted Synthesis and Mesomorphic Properties of Novel Unsymmetric Imidazolium as Ionic Liquid Crystals

2011 ◽  
Vol 181-182 ◽  
pp. 181-184
Author(s):  
Teng Zhou Yang ◽  
Rui Cheng ◽  
Xu Ying Liu ◽  
Wen Guang Wang ◽  
Jia Ling Pu
Keyword(s):  
Ionic Liquid ◽  
Liquid Crystals ◽  
Smectic Phase ◽  
Microwave Assisted Synthesis ◽  
Imidazolium Salts ◽  
Microwave Assisted ◽  
Ionic Liquid Crystals ◽  
Mesomorphic Properties ◽  
Microwave Assisted Method

Two kinds of novel unsymmetric imidazolium salts based ionic liquid crystals (1- [4-(dodecyloxy) phenyl]-3-hexyl/octyl-1H-imidazol-3-ium bromide) were efficiently prepared using a microwave-assisted method. Their mesomorphism has been fully investigated by POM and DSC. The two imidazolium salts displayed typical and good smectic phase textures.

Cyanobiphenyl versus Alkoxybiphenyl: Which Mesogenic Unit Governs the Mesomorphic Properties of Guanidinium Ionic Liquid Crystals?

2014 ◽  
Vol 67 (7) ◽  
pp. 1088 ◽  
Author(s):  
Johannes Christian Haenle ◽  
Manuel M. Neidhardt ◽  
Stuart Beardsworth ◽  
Jochen Kirres ◽  
Angelika Baro ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Liquid Crystals ◽  
Head Group ◽  
Substitution Pattern ◽  
Smectic A ◽  
Mesophase Formation ◽  
Mesogenic Unit ◽  
Ionic Liquid Crystals ◽  
Mesomorphic Properties ◽  
Thermal Stability Of

A series of phenylguanidinium salts 3·X, which are linked via an alkoxy spacer either to a 4-decyloxy- or 4-cyano-substituted biphenyl mesogen, was prepared and the mesomorphism studied. A decyloxybiphenyl core and a spacer of at least C6 chain length were required for mesophase formation. Replacement of the chloride counterion by other anions like bromide or tetrafluoroborate improved the thermal stability of the mesophase. A comparison of substitution pattern (meta v. para) on the phenyl ring revealed decreased melting and clearing points for the bent cationic head group. All guanidinium ionic liquid crystals 3 displayed only smectic A (SmA) phases. A packing model is assumed where the molecules in a bilayer stack over each other in opposite direction with interdigitated terminal decyloxy groups and spacers.

scholarly journals Ion conformation and orientational order in a dicationic ionic liquid crystal studied by solid-state nuclear magnetic resonance spectroscopy

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Debashis Majhi ◽  
Sergey V. Dvinskikh
Keyword(s):  
Ionic Liquid ◽  
Ionic Liquids ◽  
Liquid Crystals ◽  
Bond Order ◽  
Van Der Waals ◽  
Orientational Order ◽  
Smectic Phase ◽  
Side Chains ◽  
Dicationic Ionic Liquid ◽  
Ionic Liquid Crystals

AbstractIonic liquids crystals belong to a special class of ionic liquids that exhibit thermotropic liquid-crystalline behavior. Recently, dicationic ionic liquid crystals have been reported with a cation containing two single-charged ions covalently linked by a spacer. In ionic liquid crystals, electrostatic and hydrogen bonding interactions in ionic sublayer and van der Waals interaction in hydrophobic domains are the main forces contributing to the mesophase stabilization and determining the molecular orientational order and conformation. How these properties in dicationic materials are compared to those in conventional monocationic analogs? We address this question using a combination of advanced NMR methods and DFT analysis. Dicationic salt 3,3′-(1,6-hexanediyl)bis(1-dodecylimidazolium)dibromide was studied. Local bond order parameters of flexible alkyl side chains, linker chain, and alignment of rigid polar groups were analyzed. The dynamic spacer effectively “decouples” the motion of two ionic moieties. Hence, local order and alignment in dicationic mesophase were similar to those in analogous single-chain monocationic salts. Bond order parameters in the side chains in the dicationic smectic phase were found consistently lower compared to double-chain monocationic analogs, suggesting decreasing contribution of van der Waals forces. Overall dication reorientation in the smectic phase was characterized by low values of orientational order parameter S. With increased interaction energy in the polar domain the layered structure is stabilized despite less ordered dications. The results emphasized the trends in the orientational order in ionic liquid crystals and contributed to a better understanding of interparticle interactions driving smectic assembly in this and analogous ionic mesogens.

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