Utilization of infrared, Raman spectroscopy for structural analysis of alkali boro-germanate glasses

Figures & data

Figure 1. Infrared spectra of present glasses (x = 0, 5, 10, 20 and 30).

Figure 2. The de-convoluted IR spectra of (30−x)Li₂O–xNa₂O–40B₂O₃–30GeO₂ glass.

Table 1. Deconvoluted parameters of the FT-IR spectra of the xNa₂O–(30−x)Li₂O–40B₂O₃–30GeO₂ glasses under study. C is the component band center (cm⁻¹), A is the component band's relative area (percentage) and W is full width at half maxima.

X = 0			X = 5			X = 10			X = 20			X = 30
C	A	W	C	A	W	C	A	W	C	A	W	C	A	W
483	1.7	99.9	505	4.1	117	505	3.8	110	483	4.4	112	513	3.2	114
779	8.8	156	760	23.1	249	771	8.7	191	743	12.1	249	783	28	267
949	26.8	205	971	21.4	211	964	31.6	212	–	–		984	15.9	188
–	–		–	–	–	–	–	–	805	14.9	295	–	–	–
1098	12.6	139	1094	5.6	108	1108	19.1	109	1052	22.8	261	1102	5.3	106
1380	29.2	262	1363	22.1	274	1322	22.1	277	1344	21.1	281	1368	26.3	303
1555	20.7	364	1515	22.1	428	1461	14.5	333	1572	23.5	317	1531	21.3	499

Table 2. Fourier Transform Infrared allocations in (30-x)Li₂O–xNa₂O–40B₂O₃–30GeO₂ glass network.

x = 0	x = 5	x = 10	x = 20	x = 30	IR allocations
483	505	505	483	513	3 members GeO4 rings are related with symmetrical stretching vibrations of Ge–O–Ge bonds.
769	760	771	743	783	Stretching vibration of Ge–O polyhedral (GeO4).
949	971	964	805	984	Stretching vibrations of B–O bonds in BO4 units from diborate groups.
1098	1094	1108	1052	1102	Stretching vibrations of B–O bonds in BO4 units from pentaborate groups
1380	1363	1422	1344	1368	B–O bond stretching vibrations of polymerized BO3.
1555	1515	1461	1572	1531	Asymmetric stretching vibration with 3 NBO of B–O–B groups.

Figure 3. The Compositional dependency of several (1110 and 1500 cm⁻¹) IR band peak locations.

Figure 4. Raman spectra of current glass (30−x)Li₂O–xNa₂O–40B₂O₃–30GeO₂ with x = 0, 5, 10, 20, 30.

Figure 5. De-convoluted Raman spectra of present glasses using Gaussian functions.

Table 3. Deconvoluted parameters of the Raman spectra of the xNa₂O–(30−x)Li₂O–40B₂O₃–30GeO₂ glasses under present investigation.

X = 0			X = 5			X = 10			X = 20			X = 30
C	A	W	C	A	W	C	A	W	C	A	W	C	A	W
538	16.8	189	546	8.1	143	558	6.7	124	577	5.2	103	565	1	137
797	14.3	154	845	30.4	250	838	41.5	348	884	60.3	484	796	24.2	231
1040	23	270	1090	25.9	182	1095	14.4	152	1094	10.7	122	1071	35.2	225
1395	19.1	292	1294	2.5	182	1292	3.8	147	1285	4.1	143	1324	3.1	152
1514	26.8	312	1436	33.1	357	1501	33.6	453	1509	19.7	303	1501	37.5	495

Table 4. Wave numbers and allocations of Raman spectra of (30-x)Li₂O–xNa₂O–40B₂O_3–30GeO₂ present glasses.

Position of Raman band (cm^−1)	Raman allocations
538.0 ∼ 577	Ge–O–Ge bonds’ symmetrical stretching oscillations linked to 3 members’ rings of GeO4 tetrahedra.
796 ∼884	Ge–O symmetric stretching vibrations in GeO4 with one NBO and three bridging oxygens.
1040 ∼1095	B–O bonds’ stretched oscillations in unit of BO4.
1285∼1396	Vibrations of B–O^– terminal bonds of triangle BO3.
1436∼1514	B–O bond stretching vibration of polymerized BO3.

Figure 6. Normalized change of the intensity ratio (I₇₉₇/I₅₃₈) between the Raman bands situated at 797 and 538 cm⁻¹, as well as a shifting of the peak of band 538 cm⁻¹ with Na₂O content.

Table 5. Change of relative intensity I₇₉₇/I₅₃₈ with Na₂O content.

Composition  x	I797/I538	Peak position of band 538cm^−1
0	0.92	538
5	2.14	554
10	2.25	565
20	2.47	582
30	1.35	588