Atomistic models of amorphous silicon oxycarbide, a-SiCO with different compositional range between SiO2 and SiC are constructed by rapid quenching. Structural models consisting of 528–568 atoms are fully optimized by molecular mechanics based on ReaxFF force fields. The addition of carbon into SiO2 glass stiffens the network and increases the bulk modulus. For better understanding the thermodynamics properties of a-SiCO, the effect of pressure and temperature on the bulk modulus, heat capacity, Debye temperature and coefficient of thermal expansion are derived by the quasi-harmonic Debye model in virtue of standard thermodynamic relations.
References
1.
ColomboP., MeraG., RiedelR.Polymer-Derived Ceramics: 40 Years of Research and Innovation in Advanced Ceramics. Journal of the American Ceramic Society, 93(7) (2010) 1805–1837.
2.
PantanoC.G., SinghA.K., and ZhangH.X.Silicon Oxycarbide Glasses. Journal of Sol-Gel Science and Technology, 14(1) (1999) 7–25.
3.
SoraruG.D., EmanuelS.M., ColomboG.P.Chemical Durability of Silicon Oxycarbide Glasses. Journal of the American Ceramic Society, 85(6) (2002) 1529–1536.
4.
XuT.H., MaQ.S., and ChenZ.H.High-temperature behavior of silicon oxycarbide glasses in air environment. Ceramics International, 37(7) (2011) 2555–2559.
5.
XuT.H., MaQ.S., and ChenZ.H.Mechanical property and microstructure evolutions of Cf/SiOC composites with increasing annealing temperature in reduced pressure environment. Ceramics International, 38(1) (2012) 605–611.
6.
XuT.H., MaQ.S., and ChenZ.H.The effect of environment pressure on high temperature stability of silicon oxycarbide glasses derived from polysiloxane. Materials Letters, 65(11) (2011) 1538–1541.
7.
BoisL., MaquetJ., BabonneauF.Structural Characterization of Sol-Gel Derived Oxycarbide Glasses. 2, Study of The Thermal-Stability of the Silicon Oxycarbide Phase. Chemistry Materials, 7(5) (1995) 975–981.
8.
KrollP.A DFT study of amorphous silicon oxynitride. Journal of Non-Crystalline Solids, 351(12–13) (2005) 1127–1132.
9.
KrollP.A DFT study of the compressibility of amorphous silicon oxynitride. Journal of Non-Crystalline Solids, 345/346 (2004) 720–723.
10.
KrollP.Searching insight into the atomistic structure of SiCO ceramics. Journal of Materials Chemistry, 20(46) (2010) 10528–10534.
11.
KrollP.Modeling the “free carbon” phase in amorphous silicon oxycarbide. Journal of Non-Crystalline Solids, 51(12–13) (2005) 1121–1126.
12.
KrollP.Modelling and simulation of amorphous silicon oxycarbide. Journal of Materials Chemistry, 13(7) (2003) 1657–1668.
13.
van DuinA.C.T., DasguptaS., LorantF., and GoddardW.A.IIIReaxFF: A Reactive Force Field for Hydrocarbons. Journal of Physical Chemistry A, 105(41) (2001) 9396–9409.
14.
van DuinA.C.T., StrachanA., StewmanS., ZhangQ., and GoddardW.A.IIIReaxFFSiO Reactive Force Field for Silicon and Silicon Oxide Systems, Journal of Physical Chemistry A, 107(19) (2003) 3803–3811.
15.
NormanP., and SchwarztentruberT.Modeling Air-SiO2 Surface Catalysis under Hypersonic Conditions with ReaxFF Molecular Dynamics. AIAA, 2010–4320.
16.
BlancoM.A., FranciscoE., LuanaV.GIBBS: Isothermal-Isobaric Thermodynamics of Solids from Energy Curves Using a Quasi-Harmonic DEBYE Model, Computer Physics Communications., 158(1) (2004) 57–72.
BlancoM.A., Martín PendásA., FranciscoE.Thermodynamical Properties of Solids from Microscopic Theory: Applications to MgF2 and Al2O3, 368(27) (1996) 245–255.
19.
FlórezM., RecioJ.M., FranciscoE.First-principles Study of the Rocksalt-Cesium Chloride Relative Phase Stability in Alkali Halides. Physical Review B, 66(14) (2002) 144112.
20.
BrequelH., ParmentierJ., WalterS.Systematic Structural Characterization of the High-Temperature Behavior of Nearly Stoichiometric Silicon Oxycarbide Glasses. Chemistry Materials, 16(13) (2004) 2585–2598.
