Reflection loss correction method for accurate absorbance spectrum analysis of coloured glasses

Méthodes d’analyse des verres

“…Dans le cas d'un verre silicaté sodo-calcique par exemple, la fraction du signal due à la réflexion est estimée à 0,04, ce qui est relativement faible et peut-être considéré comme négligeable dans de nombreuses applications. Il existe néanmoins différentes méthodes pour corriger cet effet [26,27].…”

Vibrations and chemical states of iron ions in soda‐lime glasses determined by element‐specific X‐ray analyses

“…In the case of iron ions with M Fe2aO3 > ∼0.3 wt%, many measurements have been performed on the various types of glass fabricated under various processing conditions by using nonelement‐specific or element‐specific methods, including transmittance_ UV‐NIR measurements, X‐ray absorption fine structure (XAFS) pre‐edge (the lower energy region below the absorption edge) measurements, Mössbauer spectroscopy, neutron diffraction measurements, electron spin resonance (ESR) measurements, and nuclear magnetic resonance measurements . Some of these experimental results have not been able to be explained in terms of the commonly accepted understanding described above.…”

“…Some of these experimental results have not been able to be explained in terms of the commonly accepted understanding described above. This has led to many models having been proposed, including ones incorporating medium‐range structures around the iron ions or different/additional coordinations of iron ions . For example, they include combinations of three to five neighboring atoms around the target iron ion over the M Fe2O3 range between 0.3 and 4 wt%, such as clusters of Fe 3+ for M Fe2O3 of 1.5 wt% or higher, polymerization (clustering) with a five‐atoms combination of Fe 3+ with a 4‐coordination number of four (Fe 3+ ) with bridging oxygen (BO) to Si (Fe 3+ –BO–Fe 3+ –BO–Si), and an Fe–O–Fe structure with strong bonding .…”

“…On the other hand, the sensitivity and the element specificity of the commonly used measuring methods are poor for studying samples with lower concentrations (M Fe2O3 < ~0.1 wt%). Accordingly, there have been few reports on glass with M Fe2O3 < ~0.1 wt%.…”

“…The commonly used measuring methods described above, such as transmittance_ UV‐NIR measurements, XAFS pre‐edge measurements, Mössbauer spectroscopy, neutron diffraction measurements, ESR measurements, and nuclear magnetic resonance measurements, cannot reveal the medium‐ or short‐range structures around iron ions with low M Fe2O3 < ~0.1 wt% directly. For example, the pre‐edge shape of Fe‐ K ‐edge X‐ray absorption near edge structure (XANES) is sensitive to the first‐neighbor symmetrical structure and reflects characteristics such as the oxidization states and coordinations of only the first‐neighbor atoms around the iron ion .…”