*2.5. Thermogravimetric (TG) Analysis*

Thermogravimetric (TG) and differential thermal analysis (DTA) measurements were performed using a Thermo plus EVO (Rigaku, Tokyo, Japan). A sample of powdery 4.75H (7.856 mg) in an unsealed aluminum pan was heated at 5 ◦C min−<sup>1</sup> up to 150 ◦C under flowing N<sup>2</sup> gas (100 mL min−<sup>1</sup> ).
