A Multisurface Matrix-Isolation Apparatus

1986 ◽  
Vol 40 (5) ◽  
pp. 588-595 ◽  
Author(s):  
Robert H. Hauge ◽  
Leif Fredin ◽  
Zakya H. Kafafi ◽  
John L. Margrave

A multisurface matrix-isolation apparatus has been designed and interfaced to an FT-IR vacuum spectrometer. The design permits independent matrix-isolation studies with sixty different surfaces. It also allows direct measurement of matrix gas to guest ratios with an integral cooled quartz crystal microbalance. Problems associated with moving the matrix block while maintaining good thermal contact are discussed. Finally, some applications to studies of coal pyrolysis, metal atom chemistry, and quantitative analysis are presented.

1989 ◽  
Vol 43 (8) ◽  
pp. 1424-1427 ◽  
Author(s):  
W. M. Coleman ◽  
Bert M. Gordon

Qualitative and quantitative analysis of compounds in a complex mixture by gas chromatography/matrix isolation/Fourier transform infrared spectrometry (GC/MI/FT-IR) is described. The carbon-deuterium stretching mode was characterized and used for analysis since it has a unique position in the infrared spectrum. Compounds of varying functionalities were examined over a concentration range from 6 to 50 ng. Linear responses over this mass range were obtained. Flame ionization detection was used for collaborative detection in establishing the linearity of the responses. These results represent the first use of GC/MI/FT-IR for quantitative analysis of compounds in a complex mixture using deuterium-labeled analogues.


1988 ◽  
Vol 42 (1) ◽  
pp. 101-108 ◽  
Author(s):  
W. M. Coleman ◽  
Bert M. Gordon

Matrix isolation Fourier transform spectral evidence is presented that documents the isolation of rotational isomers in an argon matrix. The spectral evidence is based on the presence of split carbonyl absorption bands in the spectra of selected derivatives of methyl acetate which do not vary in intensity with changes in the matrix-to-eluate ratios. The results compare very favorably with FT-IR data on the identical compounds obtained in the vapor phase. The low temperature of the matrix isolation experiment (10 K) allows for the observance of rotational isomers not seen at the high temperatures of the vapor-phase experiment (500 K). The presence of multiple carbonyl absorption bands dictates that careful attention must be paid to spectral/structure correlations employing MI/FT-IR data.


1989 ◽  
Vol 43 (6) ◽  
pp. 998-1003 ◽  
Author(s):  
W. M. Coleman ◽  
Bert M. Gordon

A set of five search routines—absolute difference, absolute derivative, square difference, square derivative, and Euclidean difference—have been applied to the analysis of the matrix isolation/Fourier transform-infrared spectra (MI/FT-IR) of the components of four essential oils: coriander oil, lemon oil, geranium oil, and citronella oil. The routines were tested under a variety of parameters on a diverse set of compounds and IR spectra. Areas of acceptable performance by the routines as well as areas of marginal performance are discussed. Under the conditions of this study, the absolute derivative routine is judged to be the most acceptable of the five.


1989 ◽  
Vol 43 (6) ◽  
pp. 1004-1008 ◽  
Author(s):  
W. M. Coleman ◽  
Bert M. Gordon

Matrix isolation Fourier transform infrared spectra (MI/FT-IR) of a series of essential oil components have been described. Clear, well-defined differences were detected in the MI/FT-IR spectra of compounds having minor differences in their structure. A library search routine was found to correctly identify components of interest when visual differences were not clearly evident. The presence of discrete conformers in the argon matrix resulted in the presence of split absorptions in the carbonyl band for selected compounds.


1976 ◽  
Vol 30 (6) ◽  
pp. 573-586 ◽  
Author(s):  
Geoffrey A. Ozin

In the burgeoning field of cryochemistry, analytical spectroscopy has played an important role in helping us to understand the reactions of high temperature chemical species in low temperature condensation reactions. Reactions with transition metal atoms in particular have become an important synthetic method in inorganic and organometallic chemistry. Fascinating new compounds for which there are often no alternative methods of synthesis have been obtained by this technique. The potential importance of the work in terms of catalytic applications and chemical synthesis is very great indeed. Commercial evaporators and cryogenic equipment in compact and convenient forms are now commonly available and it will not be very long before metal vapor synthesis will enter the category of a routine laboratory procedure. Even at this early stage ICI (UK), duPont de Nemours (USA) and Merck (Germany) have initiated exploratory programs in metal vapor chemistry and it is only a matter of time before industrial evaporation plants are modified for large-scale metal vapor synthesis. As the field develops it is becoming increasingly evident that the seemingly unrelated methods of the preparative cryochemist and the matrix spectroscopist are intimately related. In areas such as reaction intermediates, product identification, reaction pathways, thermodynamics and kinetics, reaction feasibility and yields matrix and preparative cryochemistry cover much common ground. An intelligent marriage of the two techniques is proving to be most fruitful. In this survey lecture I will attempt to place in perspective some of the contributions that matrix isolation spectroscopy can make to the field of metal atom chemistry. In order to do this effectively in a 60-minute lecture I will restrict the reaction chemistry to that of Cu, Ag, and Au atoms. The areas to be described will include the controlled aggregation of transition metal atoms, the synthesis and characterization of coordinatively unsaturated transition metal molecular fragments and elusive binuclear compounds, and reaction kinetics using the matrix isolation technique.


1989 ◽  
Vol 43 (2) ◽  
pp. 305-310 ◽  
Author(s):  
W. M. Coleman ◽  
Bert M. Gordon

Matrix isolation Fourier transform infrared (MI/FT-IR) spectra have been collected on a series of internal alkenes, a series of hydroxy-substituted ketones, and a series of hydroxy-substituted esters. Assignments of double bond position and geometry are possible in the alkenes, due to the resolution of absorption bands of very similar energies. The location of the absorption bands for the alkenes was found to be very similar to the values found for the vapor-phase and condensed-phase spectra. Multiple carbonyl absorptions have been found in the MI/FT-IR spectra of the hydroxy ketones and hydroxy esters. Trends in the multiplicity of the carbonyl absorption patterns for these compounds as a function of ring size and hydroxyl carbon substitution have been used to document the presence of extensive intramolecular hydrogen bonding. The argon matrix as a phase for the study of stable organic compounds has, again, with this information, been shown to be unique.


1988 ◽  
Vol 42 (2) ◽  
pp. 304-309 ◽  
Author(s):  
W. M. Coleman ◽  
Bert M. Gordon

Matrix isolation Fourier transform infrared (MI/FT-IR) data has been presented that documents the presence of discrete conformers in an argon matrix for a series of ketones. The distribution of conformers in the matrix was related to the structure of the molecule, in that rigid structures (i.e., small rings, bicyclic systems, and unsaturated systems) displayed simple carbonyl absorption patterns relative to those of their less rigid counterparts. Also, conformer isolation was seen for halosubstituted ketones. These results are in agreement with previous findings concerning the vapor-phase (VP) spectra of these molecules.


1989 ◽  
Vol 43 (2) ◽  
pp. 298-304 ◽  
Author(s):  
W. M. Coleman ◽  
Bert M. Gordon ◽  
Brian M. Lawrence

Matrix isolation Fourier transform infrared spectra (MI/FT-IR), mass spectra (MS), carbon-13 Nuclear Magnetic Resonance (13C-NMR) spectra, condensed-phase infrared spectra, and vapor-phase infrared (IR) spectra are presented for a series of terpene compounds. Subtle differences in positional and configurational isomers commonly found with terpenes could be easily detected by the MI/FT-IR spectra. The results are comparable in some aspects to those obtainable from 13C-NMR and thin-film IR; however, most importantly, they are acquired at the low nanogram level for MI/FT-IR, as compared to the milligram level for the other techniques. These results represent an advance in the technology available for the analysis of complex mixtures such as essential oils containing terpene-like molecules.


Author(s):  
H.J. Dudek

The chemical inhomogenities in modern materials such as fibers, phases and inclusions, often have diameters in the region of one micrometer. Using electron microbeam analysis for the determination of the element concentrations one has to know the smallest possible diameter of such regions for a given accuracy of the quantitative analysis.In th is paper the correction procedure for the quantitative electron microbeam analysis is extended to a spacial problem to determine the smallest possible measurements of a cylindrical particle P of high D (depth resolution) and diameter L (lateral resolution) embeded in a matrix M and which has to be analysed quantitative with the accuracy q. The mathematical accounts lead to the following form of the characteristic x-ray intens ity of the element i of a particle P embeded in the matrix M in relation to the intensity of a standard S


BMC Chemistry ◽  
2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Ranju Bansal ◽  
Ranjit Singh ◽  
Khushpal Kaur

Abstract Background Environment-friendly fast and accurate mid-infrared spectroscopic methods have been developed for the quantitative analysis of doxorubicin hydrochloride (DOX) and arterolane maleate (ALM) in bulk and marketed formulations. Both transmittance and reflectance modes have been used for the analysis and a comparison has been drawn for better accuracy. The analytical methods were validated in accordance with International Council for Harmonisation (ICH) guidelines Results The proposed methods have been successfully developed and validated for the quantification of doxorubicin and arterolane maleate in solid bulk and dosage form. High recovery values in both the modes, while analysing DOX and ALM, indicated good accuracy of the methods. The methods showed excellent repeatability and intermediate precision [% RSD (Relative Standard Deviation < 2.0%]. The assay values of the drugs in solid dosage forms were also found close to the labelled claim. Conclusion The proposed Fourier transform infrared (FT-IR) spectroscopic methods were found to be specific, reproducible, valid and could be used as general methods for the quantification of most of the solid drug preparations such as tablets, capsules and powders.


Sign in / Sign up

Export Citation Format

Share Document