Chemistry and Biochemistry
Bayer School of Natural and Environmental Sciences
Jennifer A. Aitken
H. M. Kingston
Oxythiophosphate, monothiophosphate, humidity, phase transition, metathesis, second harmonic generation
The following dissertation focuses on the chemistry of materials incorporating the monothiophosphate anion. The monothiophosphate anion is a member of the oxythiophosphates, a family of compounds in which phosphorus is bound to both oxygen and sulfur. This chemical characteristic places the metal oxythiophosphates between the well known families of the metal phosphates and thiophosphates. While both the metal phosphates and thiophosphates have been reported numerous times in the literature, the oxythiophosphates are rare, with only 29 compounds reported prior to this dissertation. Three new monothiophosphate materials are presented in this work, as well a new polymorph of a previously known compound. LaPO3S and NdPO3S hydrates are found to mimic the structure of the orthophosphate mineral rhabdophane; FeCl3 is found to undergo a metathesis reaction with α-Na3PO3S at room temperature to produce an iron containing monothiophosphate material; and evidence of γ-Na3PO3S is presented. Water is found to play a key role in the chemistry of the monothiophosphate anion. Upon exposure to a humid atmosphere, reactions and phase transitions are found to occur, which require thermal or mechanochemical force to proceed under dry conditions. The hard/soft, acid/base chemistry of the monothiophosphate anion is also found to dominate both the products which are formed and the manner in which they oxidize or decompose.
The materials examined in this dissertation were characterized by powder X-ray diffraction, powder neutron diffraction, differential thermal analysis, thermogravimetric analysis, diffuse reflectance UV/Vis/NIR and IR, as well as photoluminescence spectroscopy. Additionally, second harmonic generation properties were measured.
Takas, N. (2008). The Synthesis and Physicochemical Characterization of New Monothiophosphate Materials (Doctoral dissertation, Duquesne University). Retrieved from https://dsc.duq.edu/etd/1264