Tellurite And Fluorotellurite Glasses For Active And Passive

5. Crystallisation studies; MDO 146
Table (5.5): Ten most intense peaks with corresponding 2θ (observed and theoretical) and
Miller indices for 99.995% ZnF2 powder after fluorination, sourced from Alfa Aesar.
Observed
2θθθθ / °
Observed
intensity / %
Theoretical
2θθθθ / °
Theoretical
intensity / %
hkl
JCPDS
Card
26.77487 100.0 26.76571 100 110 07-0214
34.35702 59.8 34.36759 95 101 "
38.23202 9.5 38.16783 18 200 "
39.46628 18.3 39.39781 25 111 "
52.22935 56.8 52.19120 80 211 "
55.02323 16.1 54.93697 25 220 "
58.68978 8.6 58.75698 18 002 "
62.07305 7.6 61.96837 14 310 "
65.44186 10.6 65.45300 12 112 "
66.19661 14.9 66.13394 20 301 "
5.2.1.2. XRD of deposits from glass melting and fluorination
Fluorination
During fluorination of ZnF2 (see section 3.4), HF, H2O, NH3 and possibly some ZnF2
were given off by the batch. The deposit left on the silica lid of the silica liner which
contained the platinum crucible and batch in the glovebox was collected for analysis. Fig.
(5.8) shows the XRD trace of this deposit. Two phases were clearly identified - JCPDS
card number 74-0944 triammonium silicon fluoride (NH4)3SiF6F, tetragonal, and JCPDS
card number 35-0758 ammonium fluoride NH4F, hexagonal, space group P63mc. Table
(5.6) shows the ten most intense peaks with corresponding 2θ (observed and theoretical),
phases and Miller indices.