Vibrational behaviour of K2HPO4, K2HPO4·3H2O and their deuterated derivatives with temperature

Vibrational spectra of α-Ge(HPO4)2·H2O compound

“…The symmetric y 1 (A) and asymmetric y 3 (F) stretching transform into two modes of the PO 3 group being one doubly degenerated y d (PO 3 ); one symmetrical y 1 (PO 3 ); and one P-OH stretching. Following the work of Hadrich et al [14], these modes are expected to be observed about 1076, 988, and 862 cm À1 , respectively. The y 2 and y 4 bending modes are expected to be observed between 300 and 500 cm À1 .…”

“…Five n 4 modes were observed at the frequencies 449, 470, 509 and 543, and 609 cm À1 . The mode assignment was performed based on the reports for others APTM and hydrogenphosphate-based compounds available in the literature [13][14][15].…”

The pH effects on the growth rate of KDP (KH2PO4) crystal by investigating Raman active lattice modes

“…The behavioral changes of the 0 1 and 0 2 modes and their effect on the 1 mode have been illustrated in Fig. 36 In the Raman spectrum of KDP aqueous supersaturated solution with pH value higher than 5.5, the intensities of 0 1 and 0 2 remains almost equal, but the intensity of the third mode, 0 3 , has always increased. These two modes in the spectra of supersaturated solutions of KDP with pH D 3.5, 4.5 and 5 and even near to pH D 5.5, have almost equal intensities and do not have significant changes in comparison with each other.…”

Synthesis, crystal structure, and vibrational study of K2Cu(HPO4)2·6H2O: A new metal hydrogenphosphate compound

“…4 and 5 (a, b, c and d)) appeared in the 3200e2400, 2370e2000, and 1750À1400 cm À1 regions, respectively. According to the correlation curve n O … Hi ns(R i ¼ O-H i … O) (i ¼ 1A, 1B, 2A, 2B, 3A and 3B) established by Choi et al [26] for some hydrogen mono-phosphates, -sulfates, and -arsenates, the extremely broad and intense A-type band could be interpreted as an overlapping of six A-type bands whose maxima corresponded to each of the six OeH … O bonds: n O … H1A (R 1A ¼ 2.65(7)Å) 3190 cm À1 , n O … H1B (R 1B ¼ 2.67(2)) ¼ 3126 cm À1 , n O … H3A (R 3A ¼ 2.72(3))~2998 cm À1 , n O … H3B (R 3B ¼ 2.76(6) Å)~2914 cm À1 , n O … H2B (R 2B ¼ 2.76(2)Å)~2867 cm À1 , and n O … H2A (R 2A ¼ 2.77(2)Å) 2456 cm À1 .…”