(R)-1-methylheptyl 4-(4′-n-dodecyloxybiphenyl-4-yl-carbonyloxy)-3-fluorobenzoate 12OF1M7

Description

(R)-1-methylheptyl 4-(4′-n-dodecyloxybiphenyl-4-yl-carbonyloxy)-3-fluorobenzoate 12OF1M7 is a calamitic (rod-shaped) mesogen based on a biphenyl core terminated by a heptyl chain, with a single lateral fluorine. Molecules of this shape share a common director, and that orientational order – fluid in position, ordered in direction – is what a liquid crystal device switches.

Key data

• Catalogue code: KC1021
• Molecular formula: C40H53FO5
• Molecular weight: 632.84 g/mol
• Category: Liquid Crystals
• Also listed as: (R)-1-methylheptyl 4-(4′-n-dodecyloxybiphenyl-4-yl-carbonyloxy)-3-fluorobenzoate

What the substitution pattern does

The heptyl chain places this compound at n=7 in its homologous series. Chain length is not a cosmetic variable here: each added methylene lowers the melting point unevenly and shifts the balance between nematic and smectic order, because an odd-numbered chain sets its terminal bond at a different angle to the molecular long axis than an even one. Homologues therefore alternate in behaviour rather than trending smoothly, and an odd-numbered member frequently outperforms both of its neighbours for a given formulation.

A single lateral fluorine is the minimal intervention available to a materials chemist: it disrupts crystal packing enough to depress the melting point and widen the usable mesophase range, while adding almost nothing to molecular width.

The biphenyl core supplies the rigid, elongated shape that mesophase formation requires. Its two rings twist out of coplanarity by roughly 40 degrees in the gas phase but flatten in condensed phases, and that adjustable conjugation is what makes biphenyls both mesogenic and optically anisotropic.

Phase behaviour

Transition sequence measured for this compound:

SmCanti* 78 SmCgamma* AF 84.5 FiLC 92 SmC* 93 SmCalpha* 94.4 SmA 106°C I

Reading that sequence, in order of increasing temperature:

• SmCanti* – antiferroelectric smectic C*
• SmCgamma* – ferrielectric smectic C*
• SmCalpha* – smectic C alpha*
• SmC* – chiral smectic C
• SmA – smectic A – layered, molecules normal to the layers
• FiLC – ferrielectric
• AF – antiferroelectric
• I – isotropic liquid

Starred phases are chiral. In a chiral smectic C the molecular tilt combines with the absence of mirror symmetry to produce a spontaneous polarisation – which is what lets a ferroelectric device be switched by the sign of the applied field rather than by its magnitude, and why switching times fall from milliseconds to microseconds.

Typical applications

• extension of rigid-core length in high-birefringence blends
• nematic and smectic host mixtures for display and photonic devices
• reference material for calibrating transition temperatures and optical measurements
• research into ferroelectric and antiferroelectric switching
• alignment-layer and surface-anchoring studies

Ordering

This compound is supplied to order. Pricing depends on quantity and on the specification you need, so it is quoted rather than listed – send an enquiry stating the quantity and any purity or analytical requirement, and you will receive a written quotation.

Handling and documentation

Supplied for laboratory and industrial use by trained personnel only. Not for use as a medicine, food, cosmetic or biocide, and not for administration to humans or animals. Safety documentation is issued with the order; this page is not a source of hazard information.