Synthesis, structure, optical, and thermal properties of diallylammonium hexabromostannate(IV) hybrid

GRAPHICAL ABSTRACT

ABSTRACT

Diallylammonium hexabromostannate(IV) was synthesized and characterized by IR, ¹H,¹³C NMR, DRS, TG-DTA, Single crystal XRD. ¹H chemical shifts of the protons in the hybrid are lower than the diallylammonium cation due to extensive hydrogen bonded and weak van der Waals interactions. The NH₂⁺ protons of the hybrid are observed as a singlet at 8.963 ppm compared to those of the diallylammonium chloride at 9.800 ppm, a significant decrease. ¹³C NMR spectrum shows a maximum downward chemical shift for α-C(H₂). DRS spectrum shows a strong charge transfer transition in the range 429 to 492 nm. The hybrid is thermally stable up to ∼195°C. Single crystal X-ray crystallography shows the asymmetric unit to be [C₆H₁₂N]⁺ 0.5[SnBr₆]²⁻. All the bromide ions are involved in hydrogen bonding. BVS of tin in diallylammonium hexabromostannate(IV) was calculated based on the Sn-Br bond distances obtained from the single crystal X-ray structural analysis as 3.941, which is close to its formal oxidation state of +4. This is the first report which clearly established the formal oxidation state of tin in a hybrid material from X-ray structural data. The CSM of SnBr₆²⁻ anion was found to be 0.0145 indicating its near perfect octahedral geometry.

KEYWORDS:

• BVS
• diallylammonium
• DRS
• hybrid material
• tin(IV)
• X-ray structure

ORCID

C. Rizzoli http://orcid.org/0000-0002-4841-6123