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  • 1 Department of Inorganic Chemistry, University of Bucharest, 23 Dumbrava Rosie st, sector 2, Bucharest 020464, Romania
  • | 2 Physics Department II, University “Politehnica Bucuresti”, Splaiul Independentei 313, Bucharest 060042, Romania
  • | 3 Centre of Organic Chemistry “C. D. Nenitzescu”, Romanian Academy, Spl. Independentei 202B, Bucharest 060023, Romania
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Abstract

A series of ortho-metallated palladium(II) complexes with two dimeric liquid crystals Schiff base (methoxy and decyloxy as terminal groups) as cyclometallated ligands and N-aryl-N′-benzoyl thiourea derivatives as co-ligands were prepared and investigated for their liquid crystalline properties. Their structures were assigned based on elemental analysis, FT-IR and 1H NMR spectroscopy while the thermal behaviour was investigated by differential scanning calorimetry and polarising optical microscopy. The complexes with Schiff base ligand bearing methoxy group as terminal group show extensive decomposition during melting while the complexes with Schiff base having decyloxy group as terminal group show monotropic nematic phases, with the mesophase stability strongly related to the type of N-aryl-N′-benzoyl thiourea derivative used. Their liquid crystalline properties are compared with their analogues having N,N-dialkyl-N′-benzoyl thiourea as co-ligands which were reported previously. One of the latter complexes was also investigated by thermally stimulated depolarisation currents method while the optical transmission was recorded simultaneously. The thermally stimulated depolarisation currents and optical transmission spectra confirmed the previous observation regarding the phase transition temperatures. The current intensity–applied voltage dependencies of this complex were investigated by specific electrical measurements.

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  • SJR Quartile Score (2018): Q2 Condensed Matter Physics
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Journal of Thermal Analysis and Calorimetry
Language English
Size A4
Year of
Foundation
1969
Volumes
per Year
4
Issues
per Year
24
Founder Akadémiai Kiadó
Founder's
Address
H-1117 Budapest, Hungary 1516 Budapest, PO Box 245.
Publisher Akadémiai Kiadó
Springer Nature Switzerland AG
Publisher's
Address
H-1117 Budapest, Hungary 1516 Budapest, PO Box 245.
CH-6330 Cham, Switzerland Gewerbestrasse 11.
Responsible
Publisher
Chief Executive Officer, Akadémiai Kiadó
ISSN 1388-6150 (Print)
ISSN 1588-2926 (Online)

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