Humidity-sensing properties of an 1D antiferromagnetic oxalate-bridged coordination polymer of iron(III) and its temperature-induced structural flexibility

Burazer, Sanja (author), Molčanov, Krešimir (author), Šantić, Ana (author), Klaser, Teodoro (author), Wenger, Emmanuel (author), Pajić, Damir (author), Jagličić, Zvonko (author), Popović, Jasminka (author), Jurić, Marijana (author)

A novel one-dimensional (1D) oxalate-bridged coordination polymer of iron(III), {[NH(CH3 ) (C2H5 )2 ][FeCl2 (C2O4 )]}n (1), exhibits remarkable humidity-sensing properties and very high proton conductivity at room temperature (2.70 × 10−4 (Ω·cm)−1 at 298 K under 93% relative humidity), in addition to the independent antiferromagnetic spin chains of iron(III) ions bridged by oxalate groups (J = −7.58(9) cm−1 ). Moreover, the time-dependent measurements show that 1 could maintain a stable proton conductivity for at least 12 h. Charge transport and magnetic properties were investigated by impedance spectroscopy and magnetization measurements, respectively. Compound 1 consists of infinite anionic zig-zag chains [FeCl2 (C2O4 )]n n− and interposed diethylmethylammonium cations (C2H5 )2 (CH3 )NH+ , which act as hydrogen bond donors toward carbonyl oxygen atoms. Extraordinarily, the studied coordination polymer exhibits two reversible phase transitions: from the high-temperature phase HT to the mid-temperature phase MT at T ~213 K and from the mid-temperature phase MT to the low-temperature phase LT at T ~120 K, as revealed by in situ powder and single-crystal X-ray diffraction. All three polymorphs show large linear thermal expansion coefficients.

• Language: English
• Keywords: oxalate-bridged coordination polymers, alkyl ammonium cations, single-crystal-to-singlecrystal transformations, proton conductivity, humidity-sensing property, antiferromagnetic spin chain
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FGG - Faculty of Civil and Geodetic Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2021
• Number of pages: 12 str.
• Numbering: Vol. 14, iss. 19, art. 5543
• PID: 20.500.12556/RUL-142038
• UDC: 544
• ISSN on article: 1996-1944
• DOI: 10.3390/ma14195543
• COBISS.SI-ID: 124821763
• Publication date in RUL: 17.10.2022

Record is a part of a journal

• Title: Materials
• Shortened title: Materials
• Publisher: MDPI
• ISSN: 1996-1944
• COBISS.SI-ID: 33588485

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.
• Licensing start date: 24.09.2021

Secondary language

• Language: Slovenian
• Keywords: koordinacijski polimeri, protonska prevodnost, detektor vlažnosti", antiferomagnetna spinska veriga

Projects

• Funder: ARRS - Slovenian Research Agency
• Project number: P2-0348
• Name: Nove slikovno-analitske metode