Potassium hydrogen maleate

X-RAY STUDIES OF AMMONIUM BIFLUORIDE, POTASSIUM HYDROGEN MALEATE,... 

The anion (11) in crystalline potassium hydrogen cis-butenedioate (potassium hydrogen maleate) closes a 7-membered ring by an internal hydrogen bond. This is very short, with O 0=2.437 A and the proton is almost certainly at the centre, the whole anion being symmetrical about a plane through the acidic hydrogen atom and middle of the double bond. 

A single crystal XH NMR study of potassium hydrogen maleate has established the chemical shift tensors of all magnetically inequivalent XH nuclei in the unit cell [131]. 

H. M. E. Cardwell, J. D. Dunitz, and L. E. Orgel. J. Chem. Soc. 1953, 3740-2. IR spectra of maleic acid (and deutero-), potassium hydrogen maleate (and deutero-), possible symmetrical H bond. 

F. Fillaux, N. Leygue, J Tomkinson, A. Cousson, W. Paulus (1999). Chem. Phys., 244, 387-403. Structure and dynamics of the s)mmetric hydrogen bond in potassium hydrogen maleate a neutron scattering study. 

An example of FDS output, for potassium hydrogen maleate at 15 K is shown in Fig. 3.17. The improved resolution of the (Be—BeO) spectrum, over the simple Be filter method, is marked. This results from two factors the narrower bandpass used in the difference spectrum and the removal of the long-time tails of the incident pulse. The long-time tails are seen illustrated in the insets in Fig. 3.17, which show the shapes of the elastic lines. The energy transfer range is 50—5000 cm , the... 

Fig. 3.17 Treatment of FDS (LANSCE) data INS time-of-flight spectrum of potassium hydrogen maleate recorded with (a) Be filter, (b) BeO filter and (c) the difference (Be-BeO). The inset in each spectrum shows the lineshape of the elastic line associated with each measurement. Reproduced from [20] with permission from Elsevier.

J. Tomkinson, I.J. Braid, J. Howard T.C. Waddington (1982). Chem. Phys., 64, 151-157. Hydrogen-bonding in potassium hydrogen maleate and some simple derivatives studied by inelastic neutron-scattering spectroscopy. 

Table 10. Some dimensions in the hydrogen-anions of potassium hydrogen maleate (by X-ray diffraction), and of potassium hydrogen cMororrtaleate (by neutron diffraction)...

H3KO4, Potassium hydrogenfumarate, 44B, 20 HaKO, Potassium hydrogen maleate, 22, 573 26, 555 HaNaO , Sodium hydrogen fumarate, 35B, 13... 

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