A note on the regular model of an absorption band

<div><div>Scattering-mode Scanning Near-Field Optical Microscopy (sSNOM) allows one to obtain absorption spectra in the mid-IR region for samples as small as 20 nm in size. This configuration has made it possible to measure FTIR spectra of the protein complement of membranes. (Amenabar 2013) We now show that mid-IR sSNOM has the sensitivity required to measure spectra of phospholipids in individual bilayers in the spectral range 800 cm<sup>-1</sup>–1400 cm<sup>-1</sup>. We have observed the main absorption bands of the dipalmitoylphosphatidylcholine headgroups in this spectral region above noise level. We have also mapped the phosphate absorption band at 1070 cm<sup>-1</sup> simultaneously with the AFM topography. We have shown that we could achieve sufficient contrast to discriminate between single and multiple phospholipid bilayers and other structures, such as liposomes. This work opens the way to further research that uses nano-IR spectroscopy to describe the biochemistry of cell membranes and model systems.</div></div><div></div>

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Remarks to localization of the absorption band of C=S and C=Se stretching vibrations in the infrared spectra of thio- and selenosemicarbazide and of their coordination compounds

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19691353 ◽

1969 ◽

Vol 34 (5) ◽

pp. 1353-1359 ◽

Cited By ~ 3

Author(s):

K. Volka ◽

Z. Holzbecher

Keyword(s):

Absorption Band ◽

Infrared Spectra ◽

Coordination Compounds ◽

Stretching Vibrations

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The effect of substitution on the frequency and intensity of the C=C double bond absorption band

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19692101 ◽

1969 ◽

Vol 34 (7) ◽

pp. 2101-2107 ◽

Cited By ~ 3

Author(s):

M. Podzimková ◽

M. Procházka ◽

M. Paleček

Keyword(s):

Double Bond ◽

Absorption Band

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A discussion on equations of phase equilibrium between two regular binary phases

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19811433 ◽

1981 ◽

Vol 46 (6) ◽

pp. 1433-1438

Author(s):

Jan Vřešťál

Keyword(s):

Phase Equilibrium ◽

Linear Function ◽

Concentration Dependence ◽

Absolute Temperature ◽

Enthalpy Change ◽

Independent Parameter ◽

Free Enthalpy ◽

Regular Solutions ◽

Regular Model ◽

Concentration Dependences

The conditions of the existence of extreme on the concentration dependences of absolute temperature (x are mole fractions) T = Tα(xkα) and T = Tβ(xkβ) denoting equilibrium between two binary regular solutions are generally developed under two assumptions: 1) Free enthalpy change of pure components k = i, j at transition from phase α to β is a linear function of temperature. 2) Concentration dependence of excess free enthalpy (identical with enthalpy) of solutions α and β, respectively, is described in regular model by one concentration and temperature independent parameter for each individual phase.

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