The dissociation energy of gaseous diatomic sulfur

1969 ◽  
Vol 47 (21) ◽  
pp. 2423-2427 ◽  
Author(s):  
J. M. Ricks ◽  
R. F. Barrow
Keyword(s):  
Long Range ◽  
Dissociation Energy ◽  
The State ◽  
Rotational Analysis ◽  
Kcal Mole ◽  
Absorption Bands

Three limiting curves of predissociation for the F1, F2, and F3 components of the state B3Zu− of S2 have been obtained following a detailed rotational analysis of emission and absorption bands of 32S2, 34S2, and 32S34S. The three curves extrapolate to identical limits, at 35 999.0 ± 2.5 cm−1 above the minimum in X3Σg−. The predissociating state is thereby identified as a 1u state, and arguments based upon (i) the noncrossing rule for states of like Ω and (ii) a comparison of the observed shapes of the limiting curves with those calculated on the basis of long-range forces, indicate that the products at this limit are S(3P2) + S(3P1). D00 (32S2) is then 35 216.4 ± 2.5 cm−1, or 100.69 ±.01 kcal mole−1.

Rotational analysis of the A-X and B-X systems of AuBe and AuMg

1965 ◽  
Vol 287 (1409) ◽  
pp. 240-258 ◽  
Keyword(s):  
Dissociation Energy ◽  
Thermal Emission ◽  
Ground States ◽  
Rotational Analysis ◽  
Kcal Mole ◽  
Electronic Band ◽  
Vibrational Levels ◽  
Two Systems

Electronic band systems of the gaseous molecules AuBe and AuMg may be observed in thermal emission or in absorption at temperatures around 2000 °C. The rotational analysis of bands of two systems of each molecule has been carried out. The ground states are 2 Σ + states, correlating with Au 2 S 1/2 and Be 1 S 0 or Mg 1 S 0 . The upper states are Ω = 1/2 states derived from Au 2 D 2 1/2 and Be 1 S 0 or Mg 1 S 0 . All the upper states show appreciable Ω-doubling. The following constants (cm-1) have been obtained: state Too A(7j Be 10® a re (A-) (i) AuBe Bh 18956-68 622-28 0-47944 4-34 2-0199 A$ 17194-88 647-57 0-49264 4-63 1-9927 X*E+ 0 600-63 0-46074 4-00 2-0605 (ii) AuMg B 19507-52 — [0-14043] — [2-3695] Ah 18409-05 — [0-14201] — [2-3562] X 2E+ 0 306-10 0-13214 0-73 2-4427 Figures in parentheses refer to v = 0. The vibrational levels in the upper states of AuBe converge rather rapidly, but only a rough estimate of the dissociation energy can be obtained: this is D 0 0 AuBe) ~ 67 kcal/mole.

FINE STRUCTURE OF THE SCHUMANN-RUNGE BANDS NEAR THE CONVERGENCE LIMIT AND THE DISSOCIATION ENERGY OF THE OXYGEN MOLECULE

1954 ◽  
Vol 32 (2) ◽  
pp. 110-135 ◽  
Author(s):  
P. Brix ◽  
G. Herzberg
Keyword(s):  
Dissociation Energy ◽  
Total Angular Momentum ◽  
Oxygen Molecule ◽  
Kcal Mole ◽  
Component Level ◽  
Absorption Bands ◽  
Precise Information ◽  
Near Ultraviolet ◽  
Triplet Splitting ◽  
The One

The Schumann-Runge absorption bands of O2[Formula: see text] have been photographed in the fourth order of a 3 m. vacuum spectrograph with a resolution of 160,000. Some spectra were taken with the O2 at liquid air temperature. A detailed line structure analysis has been carried out for all bands with ν′ > 11. In addition to the six main branches (with ΔJ = ΔN = ± 1), for low values of the quantum number N (total angular momentum apart from spin), several lines of the six satellite branches [Formula: see text] as well as of the two "forbidden" branches (with ΔN = ± 3, ΔJ = ± 1) have been identified. Values of the rotational constants and the vibrational quanta in the upper state have been derived up to ν′ = 21. The triplet splitting increases rapidly with N and with ν′; it cannot be described accurately by the known theoretical formulae.The origin of the 21–0 band is at 57115 cm−1. A very short extrapolation gives the convergence limit at 57128 ± 5 cm−1. This limit agrees excellently with the one derived from the near ultraviolet [Formula: see text] bands if it is assumed that at both limits those O atoms that are produced in the 3P state are in the lowest component level of this state, viz. 3P2. A discrepancy pointed out earlier by Herzberg is thus removed. The convergence limit just mentioned and certain other data derived from the spectrum lead to very precise information about the dissociation energy of O2. Without any extrapolation the dissociation energy into normal atoms can be given as 41260 ± 15 cm−1 (or 5.1148 ± 0.002 ev. or 117.96 ± 0.04 kcal./mole), which is 0.63% higher than the old value.

The C—Br bond dissociation energy in halogenated bromomethanes

1951 ◽  
Vol 209 (1096) ◽  
pp. 110-131 ◽  
Keyword(s):  
Bond Dissociation Energy ◽  
Dissociation Energy ◽  
Methyl Bromide ◽  
Frequency Factor ◽  
Unimolecular Dissociation ◽  
Bond Dissociation Energies ◽  
Kcal Mole ◽  
Fast Reaction ◽  
Bond Dissociation ◽  
Dissociation Energies

The pyrolyses of methyl bromide and of the halogenated bromomethanes, CH 2 CI. Br, CH 2 Br 2 , CHCl 2 .Br, CHBr 3 , CF 3 Br, CCI 3 . Br and CBr 4 , have been investigated by the ‘toluene-carrier' technique. It has been shown that all these decompositions were initiated by the unimolecular process R Br → R + Br. (1) Since all these decompositions were carried out in the presence of an excess of toluene, the bromine atoms produced in process (1) were readily removed by the fast reaction C 6 H 5 .CH 3 + Br → C 6 H 5 . CH 2 • + HBr. Hence, the rate of the unimolecular process (1) has been measured by the rate of formation of HBr. The C—Br bond dissociation energies were assumed to be equal to the activation energies of the relevant unimolecular dissociation processes. These were calculated by using the expression k ═ 2 x 10 13 exp (- D/RT ). The reason for choosing this particular value of 2 x 10 13 sec. -1 for the frequency factor of these reactions is discussed. The values obtained for the C—Br bond dissociation energies in the investigated bromomethanes are: D (C—Br) D (C—Br) compound (kcal./mole) compound (kcal./mole) CH 3 Br (67.5) CHBr 3 55.5 CH 2 CIBr 61.0 CF 3 Br 64.5 CH 2 Br 2 62.5 CCI 3 Br 49.0 CHCl 2 Br 53.5 CBr 4 49.0 The possible factors responsible for the variation of the C—Br bond dissociation energy in these compounds have been pointed out.

scholarly journals Estimation of the state of the road industry of Voronezh: ways of modernization and modern methods of its development

2018 ◽  
Vol 170 ◽  
pp. 01123
Author(s):  
Alla Polovinkina ◽  
Tatyana Sviridova ◽  
Irina Kuleshova
Keyword(s):  
Long Range ◽  
Transport System ◽  
Statistical Data ◽  
The State ◽  
The Road ◽  
Existing Problems ◽  
Modern Methods ◽  
Near Future ◽  
The City ◽  
Road System

The paper is dedicated to the estimation of the state of the road economy of Voronezh up to date. The state of the Voronezh road system is analysed, statistical data are given, and the problems of the city transport system are studied. On the basis of all the data obtained, ways to solve existing problems are proposed and long-range programs for the construction of new and reconstruction in operation roads are considered. The complex of works of the improvement state of the road system planned for the near future is described in detail.

THE INFRARED SPECTRUM AND THERMAL DECOMPOSITION OF HYDRAZINE PERCHLORATE HEMIHYDRATE

1966 ◽  
Vol 44 (20) ◽  
pp. 2435-2443 ◽  
Author(s):  
P. W. M. Jacobs ◽  
A. Russell-Jones
Keyword(s):  
Infrared Spectrum ◽  
Reaction Mechanisms ◽  
Low Temperatures ◽  
Room Temperature ◽  
Kcal Mole ◽  
Absorption Bands ◽  
Kinetics Of Decomposition ◽  
Salt Melts ◽  
Chemical Equation ◽  
Kinetics Of

The infrared spectrum of hydrazine perchlorate hemihydrate (HPH) has been determined and an assignment of the absorption bands made. Invacuo, HPH will partially dehydrate even at room temperature; when heated the remainder of the half-mole of water is lost at 61 °C. The dehydrated salt melts at 138 °C and decomposition ensues. The kinetics of decomposition may be followed in the temperature range 180–280 °C. The activation energy is 36.3 kcal/mole. At low temperatures the decomposition is represented by the chemical equation[Formula: see text]but when the temperature is high enough the rate of decomposition of the ammonium perchlorate formed becomes appreciable also. Possible reaction mechanisms are discussed.

THE THERMAL DECOMPOSITION OF PERACETIC ACID IN THE VAPOR PHASE

1963 ◽  
Vol 41 (7) ◽  
pp. 1819-1825 ◽  
Author(s):  
C. Schmidt ◽  
A. H. Sehon
Keyword(s):  
Thermal Decomposition ◽  
Vapor Phase ◽  
Dissociation Energy ◽  
Peracetic Acid ◽  
Kcal Mole ◽  
Temperature Range ◽  
Primary Reactions

The thermal decomposition of peracetic acid in a stream of toluene was studied over the temperature range 127–360 °C. The main products of the reaction were CO2, CH3COOH, C2H6, CH4, HCHO, O2, and traces of CO. Dibenzyl was also formed.The overall decomposition of peracetic acid was partly heterogeneous and was represented by the two parallel primary reactions[Formula: see text] [Formula: see text]The dissociation energy of the O—O bond in peracetic acid was estimated to be 30–34 kcal/mole.

Determination of the heat of formation of trimethylindium and calculation of the mean In—CH3 bond dissociation energy

1968 ◽  
Vol 46 (10) ◽  
pp. 1633-1634 ◽  
Author(s):  
W. D. Clark ◽  
S. J. W. Price
Keyword(s):  
Bond Dissociation Energy ◽  
Dissociation Energy ◽  
Chloroform Solution ◽  
Kinetic Studies ◽  
Heat Of Formation ◽  
Enthalpy Of Reaction ◽  
Kcal Mole ◽  
Bond Dissociation ◽  
The Mean

The enthalpy of reaction of In(CH3)3,c with a chloroform solution of bromine is −162.5 kcal mole−1. With this value ΔHf0298[In(CH3)3,c] = 29.5 kcal mole−1 and ΔHf0298[In(CH3)3,g] = 41.1 kcal mole−1. Combining the latter with ΔHf0298[CH3,g] = 33.2 kcal mole−1 and ΔHf0298[In,g] = 58.2 kcal mole−1 then gives E(In—CH3) = 38.9 kcal mole−1. From previous kinetic studies D[(CH3)2In—CH3] + D[In—CH3] = 87.9 kcal mole−1. Hence D[CH3In—CH3] = 28.8 kcal mole−1.

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