Thermal properties of mixed-ligand magnesium complexes with beta-diketonates and diamimes as potential MOCVD precursors

• Published in: Journal of thermal analysis and calorimetry 2014-11, Vol.118 (2), p.849-856
• Main Authors: Vikulova, Evgeniia S., Zherikova, Kseniya V., Korolkov, Ilia V., Zelenina, Ludmila N., Chusova, Tamara P., Sysoev, Sergey V., Alferova, Nina I., Morozova, Natalia B., Igumenov, Igor K.
• Format: Article
• Language: English
• Subjects: Analysis; Analytical Chemistry; Calorimetry; Chemical vapor deposition; Chemistry; Chemistry and Materials Science; Entropy; Inorganic Chemistry; Magnesium; Measurement Science and Instrumentation; PDA; Phase transformations; Physical Chemistry; Polymer Sciences; Thermal properties; Thermodynamics; Vapor pressure
• ISSN: 1388-6150; 1588-2926; 1572-8943
• DOI: 10.1007/s10973-014-3997-7

The series of adducts of magnesium beta-diketonates with diamimes namely Mg(thd) 2 (tmeda) 1 and four new complexes Mg(thd) 2 (tmpda) 2 , Mg(thd) 2 (pda) 3 , Mg(ptac) 2 (tmeda) 4 , Mg(tfac) 2 (tmeda) 5 [beta-diketonates = R 1 C(O)CHC(O)R 2 : thd (R 1  = R 2  =  t Bu), ptac (R 1  =  t Bu, R 2  = CF 3 ), tfac (R 1  = Me, R 2  = CF 3 ); diamines = R 2 N(CH 2 ) n NR 2 : tmeda ( n  = 2, R = Me), tmpda ( n  = 3, R = Me), pda ( n  = 3, R = H)] were synthesized in order to investigate the influence of both ligand types on the thermochemical properties of these compounds. The thermal behavior of the complexes in the condensed phase was investigated by thermogravimetry and differential scanning calorimetry; the thermodynamic parameters of phase transitions were determined. The saturated vapor pressure of solid complexes Mg(thd) 2 (tmeda) and Mg(tfac) 2 (tmeda) were measured by the transmission method giving the enthalpies and entropies of sublimation processes. The reliable thermodynamic data for compound Mg(thd) 2 (tmeda) were obtained with the assistance of X-ray diffraction and the static method of saturated and unsaturated vapor pressure measurements.