Details

Autor(en) / Beteiligte

• Panicker, Lata
• Sakuntala, T.

Titel

Spectroscopic investigation of order-disorder phase transition in 4-carboxyanilinium nitrate

Ist Teil von

• Journal of molecular structure, 2021-11, Vol.1244, p.131011, Article 131011

Ort / Verlag

Elsevier B.V

Erscheinungsjahr

2021

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• •Effect of deuteration on the reversible order-disorder phase transition in 4-Carboxyanilinium Nitrate (4-CAN) is reported.•Vibration band assignment of 4-CAN was carried out by comparing its spectrum with that of the partially deuterated 4-CAN and reported assignment of the parent compounds para aminobenzoic acid and HNO3.•From temperature dependent IR study, the differences in the spectrum of 4-CAN in monoclinic and orthorhombic phases were identified. These changes are corroborated with the changes in hydrogen bonding interaction reported for the single crystal structure studies of 4-CAN. Co-crystal 4-carboxyanilinium nitrate (4-CAN) and its deuterated counterpart d4-CAN were studied using vibrational spectroscopy. This study is carried out to understand (i) the intra-and inter-molecular interactions in the co-crystals, 4-CAN in comparison with the parent compounds and (ii) which vibration bands of 4-CAN are affected on structural transition from monoclinic to orthorhombic phases. The Raman and infrared vibrational frequencies of 4-CAN and d4-CAN were assigned using the known frequencies of para-amino benzoic acid (PABA), partially deuterated PABA (dPABA) and HNO3. Close comparison of the spectral features of PABA and 4-CAN suggest a stronger NH…O hydrogen bond interaction and a relatively weaker hydrogen-bond interaction with the carbonyl group in 4-CAN. Temperature dependent IR study of 4-CAN across the order-disorder structural transition indicated that the vibrational bands of -NH3+ and -COOH moieties of 4-CAN are affected due to the changes taking place in hydrogen bond interaction. Present results corroborate well with the reported structural data of 4-CAN. [Display omitted]