Infrared Spectra of Globular Proteins in Aqueous Solution

The infrared spectra of the formate, acetate, and oxalate ions have been obtained for both the solid and aqueous solution. The Raman spectra of these ions with depolarization ratios have been obtained in aqueous solution. Vibrational assignments have been made which differ slightly for the acetate ion and more markedly for the oxalate ion from earlier work. The depolarization ratios confirm Fonteyne’s assignment for the formate ion.

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Dodekaeder und Archimedisches Antiprisma als Molekülstrukturen bei Oktacyanokomplexen des Molybdän(IV) und Wolfram(IV)

Zeitschrift für Naturforschung A ◽

10.1515/zna-1968-0612 ◽

1968 ◽

Vol 23 (6) ◽

pp. 853-860 ◽

Cited By ~ 4

Author(s):

Edgar König

Keyword(s):

Aqueous Solution ◽

Infrared Spectra ◽

Conclusive Evidence ◽

Molecular Symmetry ◽

Packing Effects

Infrared spectra (300—4000 cm-1) have been measured on the octacyanide complexes K4Mo (CN)8·2H2O and K4W (CN)8·2 H2O in aqueous solution, in the solid dihydrates, and in the solid anhydrous compounds. Comparison with relevent Raman data, particularly in the 2100 cm-1 region, provides conclusive evidence for the effective molecular symmetry of the M (CN)84- group in the different surroundings. In aqueous solution, the ions [Mo (CN)8]4- and [W (CN) 8] 4- assume the symmetry of an Archimedean antiprism, D4d . In the dihydrate crystals, the groups Mo (CN)84- and W (CN)84- approach the full D2d symmetry of a dodecahedron with triangular faces, possibly slightly distorted by packing effects. In the anhydrous compounds, the symmetry of these groups is considerably lower, very likely C8. Reasonable assignments for all normal frequencies in the 2100 cm-1 region are proposed, both in D4d and D2d symmetry.

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The coordination of β-amino ketoximes with divalent iron, cobalt, nickel and zinc

Australian Journal of Chemistry ◽

10.1071/ch9782409 ◽

1978 ◽

Vol 31 (11) ◽

pp. 2409 ◽

Cited By ~ 11

Author(s):

HKJ Powell ◽

JM Russell

Keyword(s):

Aqueous Solution ◽

Hydrogen Bonding ◽

Stability Constant ◽

Methyl Ether ◽

Infrared Spectra ◽

Iron Cobalt ◽

Divalent Iron ◽

Cobalt Nickel ◽

Stability Order ◽

The Stability

The iron(II), nickel(II) and zinc(II) complexes of the diamine dioxime ligand 4,4,9,9-tetramethyl-5,8-diazadodecane-2,11-dione dioxime (H2dddo) and the cobalt(II), nickel(II) and zinc(II) complexes of its O-methyl ether (Hddmo) have been studied potentiometrically at 25°C, I 0.10M NaCl. Stability constant data are compared with those obtained for the copper(II) and cobalt(II) complexes of H2dddo and the copper(II) complexes of Hddmo. H2dddo coordinates in the oxime-oximato form [M(Hdddo)]+ with iron(II), cobalt(II), nickel(II) and zinc(II) Hddmo forms complexes with the ligand coordinated in the oxime form [M(Hddmo)]2+ and the oximato form [M(ddmo)]+. The complexes [Zn(Hddmo)2]2+, [Zn(Hddmo)(ddmo)]+ and [Co(ddmo)(OH)] were also characterized in aqueous solution. The stability order FeII < CoII < NiII < CuII > ZnII was observed for the formation of 1 : 1 complexes with the ligands Hdddo- (log K = 8.8, 11.7, 15.2, 23.3, 12.0 for Fe to Zn respectively) and Hddmo (5.7, 6.6, 12.1, 5.3 for Co to Zn). The infrared spectra of the complexes [Ni(Hdddo)] ClO4,H2O and [Zn(Hdddo)] ClO4 are discussed in terms of oxime-oximato hydrogen bonding.

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Report Paper 4: Determination of Bonds between Metal Ions and Additives by Means of Surface Pressure and Infrared Spectra

Proceedings of the Institution of Mechanical Engineers Conference Proceedings ◽

10.1243/pime_conf_1969_184_388_02 ◽

1969 ◽

Vol 184 (12) ◽

pp. 201-206

Author(s):

S. Friberg ◽

H. Müller

Keyword(s):

Aqueous Solution ◽

Metal Ions ◽

Infrared Spectra ◽

Surface Pressure ◽

Metal Ion ◽

Specific Information ◽

Bond Properties ◽

Monomolecular Layers ◽

Surface Balance

A surface balance of the Langmuir type was used to determine the effect of different metal ion specia in an aqueous solution on the surface pressure of monomolecular layers of additives. To gain more specific information about the bond properties, the monolayers were collected and the infrared spectra recorded. It is suggested that the results can be used as data when the bonds between the additives and the atom groups on a metal surface are being considered.

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Coordination compounds of norbornadiene with silver tetrafluoroborate

Canadian Journal of Chemistry ◽

10.1139/v68-022 ◽

1968 ◽

Vol 46 (2) ◽

pp. 117-124 ◽

Cited By ~ 4

Author(s):

Harold W. Quinn

Keyword(s):

Aqueous Solution ◽

Aqueous Solutions ◽

Infrared Spectra ◽

Coordination Compounds ◽

X Ray Diffraction ◽

X Ray ◽

Hydrated Complexes ◽

Crystalline Complexes Of

Crystalline complexes of norbornadiene with silver tetrafluoroborate have been obtained both from anhydrous and aqueous solution. While both solutions yield complexes of stoichiometry AgBF4•C7H8 and 2AgBF4•3C7H8, those from the aqueous solutions also contain water of crystallization. The infrared spectra show that norbornadiene is similarly complexed in both the anhydrous and hydrated complexes but that the coordination in the 1:1 complex is different from that in the 2:3 complex. The anhydrous and hydrated 1:1 complexes have the same X-ray diffraction powder patterns while those of 2:3 complexes are different.

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The unfolding effects on the protein hydration shell and partial molar volume: a computational study

Physical Chemistry Chemical Physics ◽

10.1039/c6cp05029h ◽

2016 ◽

Vol 18 (40) ◽

pp. 28175-28182 ◽

Cited By ~ 7

Author(s):

Sara Del Galdo ◽

Andrea Amadei

Keyword(s):

Aqueous Solution ◽

Computational Analysis ◽

Computational Study ◽

Hydration Shell ◽

Partial Molar Volumes ◽

Globular Proteins ◽

Protein Hydration ◽

Native Protein ◽

Unfolded State ◽

Protein Hydration Shell

In this paper we apply the computational analysis recently proposed by our group to characterize the solvation properties of a native protein in aqueous solution, and to four model aqueous solutions of globular proteins in their unfolded states thus characterizing the protein unfolded state hydration shell and quantitatively evaluating the protein unfolded state partial molar volumes.

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Spectral Investigation of Stability of the Peroxo Complexes M2[V2O2(O2)4H2O] . aq (M = N(CH3)4, N(C4H9)4) in Solutions

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19960868 ◽

1996 ◽

Vol 61 (6) ◽

pp. 868-876 ◽

Cited By ~ 5

Author(s):

Peter Schwendt ◽

Karol Liščák

Keyword(s):

Aqueous Solution ◽

Heavy Water ◽

Infrared Spectra ◽

Electronic Spectra ◽

Asymmetric Structure ◽

Simultaneous Presence ◽

Peroxo Complexes ◽

Concentrated Solutions ◽

Nmr Spectrum ◽

Unidentified Species

Infrared spectra of solutions of M2[V2O2(O2)4H2O] . aq (M = N(CH3)4, N(C4H9)4) in heavy water and acetonitrile indicate that in concentrated solutions (c >= 0.5 mol dm-3) the asymmetric structure of the [V2O2(O2)4H2O]2- anion remains preserved for some time. Electronic spectra suggest that in more dilute solutions (c = 10-3-10-4 mol dm-3) of the M2[V2O2(O2)4H2O] . aq complexes in water and acetonitrile the dinuclear ion decomposes faster to [VO(O2)2H2O]-, followed by a relatively slow liberation of the peroxidic oxygen and formation of vanadate ions. The dinuclear complex is more stable in dilute chloroform solutions. The 51V NMR spectrum of an aqueous solution of [N(CH3)4]2[V2O2(O2)4H2O] (c = 1.3 mol dm-3) taken after a partial decomposition suggests the simultaneous presence of [V2O2(O2)4H2O]2-, [VO(O2)2H2O]-, (VnO3n)n- (n = 4, 5, 6), [HmV10O28](6-m)-, and other unidentified species.

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