The nature of fluorine in amorphous silica

Repressing oxidative wear within Si doped DLCs

“…Si is known to form many glasses based around silica and silicate chemistry. There are many examples of doped silicate glasses that exhibit different properties, an example of this is F doped a-SiO2 (47). This specific glass exhibits good chemical durability at the cost of low mechanical strength (48,49).…”

“…This specific glass exhibits good chemical durability at the cost of low mechanical strength (48,49). Structurally, the F doped glass is different to other glasses in that the fluorine inclusion depolymerises the silicate network ( Figure 10) via non bridging fluorine, which helps to remove strained bonds (47). Stress within the silicate network is known to play a key role in the degradation of the Si-O-Si chain (40,50).…”

Optical and photonic material hardness for energetic environments

“…4(B) shows the EPR spectrum of preform sample after exposure of 8×10 3 J/cm 2 . Many authors showed that in the UV-visible range the response of pure silica core fibers under ionizing radiation is compromised by the presence of the pair Non Bridging Oxygen Hole Center (NBOHC) (≡Si-O • ) and E center (≡Si •• ) [8,22], originating from the rupture of the so called "strained bonds" (≡Si-O ) [18,20]. Furthermore in our preform samples after irradiation exposure only E centers are detected.…”

“…Recently it was enlighten the resistance properties of F-doped materials under radiation exposure of different nature [18][19][20][21]. From this findings we thought to produce a new fiber generation, as described in Section 2, in which F is introduced not only in the cladding, but also in the core part.…”

Improvement of Vacuum-Ultraviolet Transparency of Silica Glass by Modification of Point Defects(Review)

“…, a part of silicon atoms can be five-coordinated with one fluorine and four bridging oxygen atoms. 42 …”