Revealing the crystal structures and relative dielectric constants of fluorinated silicon oxides

Abstract

In this work, we show that the levels of fluorine doped into silica are high enough and we have predicted some hitherto unknown fluorinated silica with expected properties.

Predicting Diamond-like Nitrides as Infrared Nonlinear Optical Materials with High Thermal Conductivity

“…And the enthalpy difference based on the lowest enthalpy of the other structures is less than 0.1 eV/atom, which is taken as the guiding principle to estimate the possibility of experimental synthesis. 61,62 And four structures Pna2 1 -MgGeN 2 , 63 Pbca-CaSiN 2 , 64 P2 1 /c-SrSiN 2 , 64 and I4̅ 2d-CaGeN 2 65 have been reported in ICSD, which indicates the reliability of our prediction. Interestingly, the predicted structure Pna2 1 -CaSiN 2 has a lower enthalpy than that of the experimental structure Pbca-CaSiN 2 , the enthalpy difference is 0.0027 eV/atom.…”

“…The other BaGeN 2 structures with the symmetries of I 4̅2 d , Pbca , Pna 2 1 , Fmm 2, and C 2 have enthalpy differences of 0.0567, 0.0619, 0.0629, 0.0791, and 0.0898 eV/atom compared with the Cmca structure. For target structures Pna 2 1 -SrGeN 2 and Pna 2 1 -BaGeN 2 , their enthalpy differences are 0.0197 and 0.0629 eV/atom less than the guiding principle of 0.1 eV/atom, which implies that they are experimentally synthesizable. , …”

“…For target structures Pna2 1 -SrGeN 2 and Pna2 1 -BaGeN 2 , their enthalpy differences are 0.0197 and 0.0629 eV/ atom less than the guiding principle of 0.1 eV/atom, which implies that they are experimentally synthesizable. 61,62 The formation enthalpies of Pna2 1 -CaSiN 2 and I4̅ 2d-A II GeN 2 (A II = Mg, Ca) under the reaction pathways (1/3) A II 3 N 2 + (1/3)M 3 N 4 = A II MN 2 were calculated as shown in Table 1. While the formation enthalpy of Pna2 1 -SrSiN 2 and Pna2 1 -A II GeN 2 (A II = Sr, Ba) is not provided because of the lack of the thermodynamically stable elementary substances Sr 3 N 2 and Ba 3 N 2 .…”

Porous Low‐Loss Silica–PMMA Dielectric Nanocomposite for High‐Frequency Bullet Lens Applications

“…Synthesis method ε r References Silica -3.9-4.5 [12] Fluorosilicate glass F-doping 3.6-3.8 [12] Fluorosilicate glass F-doping 2.8 [13] Porous silica Template-assisted synthesis 1.9 [14] Porous silica CVD and thermal decomposition 2.2 [15] Fluorinated silica-PI composite Chemical decomposition and grafting 2.6 [16] Silica-PI composite Template-assisted synthesis and thermal polymerization 2.1 [17] Porous silica-PMMA composite Template-assisted synthesis and thermal polymerization 2.7 [18] PTFE-silica composite Sintering 1.9 [19] Jem-2200FS) were used to analyze the morphology and microstructure of the synthetized materials. To determine the size distribution of the obtained polymer template spheres, silica-coated polymer spheres, and hollow silica nanoshells, Fiji ImageJ software was used to analyze FESEM and TEM images of 100 particles of each.…”

“…[11] Among dielectrics, silica has good electromagnetic properties (ε r = 3.8 and tan δ = 0.005 at 300 GHz) and thus it is a popular choice of structural materials in high-frequency applications. Lowering ε r and tan δ of SiO 2 can be achieved by 1) partially replacing easy-to-polarize Si─O bonds with Si─F bonds (e.g., by F doping); [12,13] 2) introducing voids (e.g., pores filled DOI: 10.1002/adpr.202200208 Several devices of the future generation wireless telecommunication technologies that use bands in THz frequencies for data transmission need low-loss and lowpermittivity materials to enable ideal conditions for the propagation of electromagnetic waves. Herein, a lightweight dielectric bullet-shaped lens operating in the frequency range of 110-170 GHz is demonstrated to collimate electromagnetic waves, thus increasing the intensity of the electric field.…”