Polymorphic transitions in organic crystals

Petropavlov, N.N.; Tsygankova, I. G.

doi:10.1107/s0108767384095623

Cited by 4 publications

(9 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Measurements gave a value for the enthalpy of fusion of ∆ crI l H m (glutaric acid, 371 K) ) 23.0 ( 0.5 kJ mol -1 (Table 8). Petropavlov et al 69 determined a transition for glutaric acid at 338 K with the enthalpy of transition 2.4 kJ mol -1 . In a DSC study of phase transitions in aliphatic dicarboxylic acids, Cingolani and Berchiesi 70 measured an enthalpy of transition of 2.464 kJ mol -1 at 348.5 K and an enthalpy of fusion of 20.9 kJ mol -1 for a fusion temperature of 371.0 K. As noted in the Introduction, an effusion apparatus was never completely functional in time for completion of measurements on the dicarboxylic acids within this project.…”

Section: Resultsmentioning

confidence: 99%

Thermodynamic Properties and Ideal-Gas Enthalpies of Formation for 1,4-Diisopropylbenzene, 1,2,4,5-Tetraisopropylbenzene, Cyclohexanone Oxime, Dimethyl Malonate, Glutaric Acid, and Pimelic Acid

Steele¹,

Chirico²,

Cowell³

et al. 2002

J. Chem. Eng. Data

View full text Add to dashboard Cite

The results of a study aimed at improvement of group-contribution methodology for estimation of enthalpies of formation in the ideal-gas state for pure organic substances are reported. Specific weaknesses where particular group-contribution terms were unknown, or estimated because of lack of experimental data, are addressed by experimental studies of enthalpies of combustion in the condensed phase, vaporpressure measurements, and differential scanning calorimetric (DSC) heat-capacity measurements. Enthalpies of formation in the condensed phase were determined for 1,4-diisopropylbenzene, 1,2,4,5tetraisopropylbenzene, dimethyl malonate, glutaric acid, pimelic acid, and cyclohexanone oxime. Idealgas enthalpies of formation for each of the compounds except pimelic acid are also reported. Enthalpies of fusion and for crystalline phase transitions were determined for 1,2,4,5-tetraisopropylbenzene, cyclohexanone oxime, glutaric acid, and pimelic acid. Two-phase (solid + vapor) or (liquid + vapor) heat capacities were determined from 300 K to the critical region or earlier decomposition temperature for all the title compounds. For 1,4-diisopropylbenzene, 1,2,4,5-tetraisopropylbenzene, and dimethyl malonate, values of the critical temperature and critical density were determined from the DSC results and the corresponding critical pressure was derived from the fitting procedures. The results of all the measurements were combined to derive a series of thermophysical properties including critical temperature, critical density, critical pressure, acentric factor, enthalpies of vaporization (restricted to within (50 K of the temperature range of the vapor pressures), and heat capacities along the saturation line. Wagner-type vapor-pressure equations were derived for each compound. Enthalpies of sublimation were derived for cyclohexanone oxime and, using literature vapor pressures, glutaric acid. Group-additivity enthalpy of formation parameters and strain energies useful in the application of ideal-gas-phase group-contribution correlations were derived. Errors in the literature data for the enthalpy of formation of diethyl malonate are noted.

show abstract

Section: Resultsmentioning

confidence: 99%

Thermodynamic Properties and Ideal-Gas Enthalpies of Formation for 1,4-Diisopropylbenzene, 1,2,4,5-Tetraisopropylbenzene, Cyclohexanone Oxime, Dimethyl Malonate, Glutaric Acid, and Pimelic Acid

Steele¹,

Chirico²,

Cowell³

et al. 2002

J. Chem. Eng. Data

View full text Add to dashboard Cite

show abstract

“…According to the literature, five of the compounds studied in this work present solid−solid transitions, namely, [Ch]Cl, 64,65 oxalic, 66 malonic, 35,66,67 succinic, 35 and glutaric acids. 35,66,68 For [Ch]Cl there are no values of the transition enthalpy reported in literature while for succinic acid the transition temperature is lower than the eutectic point of the binary system [Ch]Cl + succinic acid. For the remaining acids, the solid−solid transitions were not included given that the transition enthalpies typically reported are within the uncertainty of the fusion enthalpy.…”

Section: Methodsmentioning

confidence: 99%

“…Equation 9 neglects the existence of any solid−solid transitions, but some of the studied components do show polymorphic behavior. According to the literature, five of the compounds studied in this work present solid−solid transitions, namely, [Ch]Cl, 64,65 oxalic, 66 malonic, 35,66,67 succinic, 35 and glutaric acids. 35,66,68 For [Ch]Cl there are no values of the transition enthalpy reported in literature while for succinic acid the transition temperature is lower than the eutectic point of the binary system [Ch]Cl + succinic acid.…”

Section: Theoretical Backgroundmentioning

confidence: 99%

“…The activity coefficients of a component k in the liquid phase, which are a function of temperature and composition, are obtained from an EoS as the ratio between the fugacity coefficients of component k in the mixture and that of the pure compound, as follows: Equation neglects the existence of any solid–solid transitions, but some of the studied components do show polymorphic behavior. According to the literature, five of the compounds studied in this work present solid–solid transitions, namely, [Ch]Cl, , oxalic, malonic, ,, succinic, and glutaric acids. ,, …”

Section: Theoretical Backgroundmentioning

confidence: 99%

See 1 more Smart Citation

The Role of Polyfunctionality in the Formation of [Ch]Cl-Carboxylic Acid-Based Deep Eutectic Solvents

Crespo

Silva

Martins

et al. 2018

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

Aiming at providing an extensive characterization of the solid−liquid equilibria (SLE) of deep eutectic solvents (DESs), the phase diagrams of nine eutectic mixtures composed of choline chloride ([Ch]Cl) and (poly)carboxylic acids, commonly reported in the literature as DESs, were measured experimentally. Contrarily to the behavior reported for eutectic mixtures composed of [Ch]Cl (hydrogen-bond acceptor, HBA) and monofunctional hydrogen-bond donors (HBD) such as fatty acids and fatty alcohols, which have recently been shown to be almost ideal mixtures, a significant decrease of the melting temperature, at the eutectic point, was observed for most of the systems studied. This melting temperature depression was attributed to a pronounced nonideality of the liquid phase induced by the strong hydrogen-bond interactions between the two mixture components. Perturbed-chain statistical associating fluid theory (PC-SAFT) was used to describe these interactions physically. PC-SAFT allowed accurately modeling the experimental phase diagrams over the entire concentration and temperature ranges. Depending on the kind of mixture, up to two temperature-independent binary interaction parameters between HBA and HBD were applied. The PC-SAFT approach was used to provide trustworthy information on the nonideality of the liquid phase (expressed as the activity coefficients of HBA and HBD) as well as to estimate the eutectic points coordinates. The experimental data along with the modeling results allowed us to infer about the importance of the HBD's chemical structure on the formation of [Ch]Cl-based DESs.

show abstract

“…As for the temperatures and enthalpies of fusion of the four substances, a comparison was made with literature values. ,,− ,,,, Apart from the work by Dworkin et al . on 1,4-dichlorobenzene, this comparison turned out not to be very significant because most of the data were measured with less-sensitive techniques and/or no experimental errors were given; we refer to the thesis by van der Linde 12 for further details.…”

Section: Resultsmentioning

confidence: 99%

Low-Temperature Heat Capacities and Derived Thermodynamic Functions of 1,4-Dichlorobenzene, 1,4-Dibromobenzene, 1,3,5-Trichlorobenzene, and 1,3,5-Tribromobenzene

et al. 2004

View full text Add to dashboard Cite

The heat capacities of 1,4-dichlorobenzene, 1,4-dibromobenzene, and 1,3,5-trichlorobenzene from 5 K to 380 K and 1,3,5-tribromobenzene from 5 K to 410 K were measured by adiabatic calorimetry. The experimental data were used to calculate the molar entropy and enthalpy values relative to 0 K. Apart from 1,4-dichlorobenzene, the substances do not show any solid-solid transitions. Molar enthalpies of fusion and melting-point temperatures were determined. The results, given in order, are (17 907

show abstract

Polymorphic transitions in organic crystals

Cited by 4 publications

References 0 publications

Thermodynamic Properties and Ideal-Gas Enthalpies of Formation for 1,4-Diisopropylbenzene, 1,2,4,5-Tetraisopropylbenzene, Cyclohexanone Oxime, Dimethyl Malonate, Glutaric Acid, and Pimelic Acid

Thermodynamic Properties and Ideal-Gas Enthalpies of Formation for 1,4-Diisopropylbenzene, 1,2,4,5-Tetraisopropylbenzene, Cyclohexanone Oxime, Dimethyl Malonate, Glutaric Acid, and Pimelic Acid

The Role of Polyfunctionality in the Formation of [Ch]Cl-Carboxylic Acid-Based Deep Eutectic Solvents

Low-Temperature Heat Capacities and Derived Thermodynamic Functions of 1,4-Dichlorobenzene, 1,4-Dibromobenzene, 1,3,5-Trichlorobenzene, and 1,3,5-Tribromobenzene

Contact Info

Product

Resources

About