Lithium, thermodynamic data

Recently a convenient and precise method has been devised for the determination of thermodynamic data for copper (I)-olefin complexes 67> based on the coulometric generation of Cu(I) and potentiometric measurement of the Cu(I) activity in a lithium perchlorate-2-propanol medium. The formation constants for the reaction Cu(I) (2-propanol) + olefin (2-propanol) Cu(I) olefin (2-propanol), were found to be linearly related to those of the corresponding... 

This reaction results in an equilibrium potassium vapor pressure (calculated from thermodynamic data) of 0.714 torr above the LiCl-KCl eutectic at 427°C (700°K). Metallic lithium is rapidly lost, by Reaction 1, from the lithium electrode in open cells exposed to an inert atmosphere of helium (3). However, this reaction has not been evident in hermetically sealed cells. 

There is evidence for a more complex discharge mechanism via lithium intercalation into (CF,) , yielding ternary compounds, (CLiyFJ 0,34.36 -pjjg interplanar distance in (CFj) increases during reduction and may reach 935 pm . Moreover, the open-cell voltage of the redox couple (CFj) /Li is only 3 V, whereas 4.57 V is calculated from thermodynamic data via Eq. (b) . ... 

The phase diagram of the Li-Ii3N system was first described by Bol shakov, Fedevov, and Stepina,16 while exact thermodynamic data for Li3N are reported by Yonco, Veleckis, and Maroni.14 Lithium nitride forms a simple eutectic with Li with the eutectic point near 0.05 mole % Li3N at 180.3°. The melting point of Li3N is 813 1°. 

The dynamics of bimolecular C-Li exchange in several allylic lithium compounds with ligands tethered at C2 has been investigated by Fraenkel et alF by the use of the Li-C couplings yielding the thermodynamic data of this process. 

The interest in the analysis of the dependencies of equilibrium potential on composition of cathode materials for lithium-metal cells appeared in the late-1970s [2-8] where phase composition and phase transitions of oxides and hal-cogenides of transient metals upon lithiation were discussed. The usefulness of the simultaneous scrutiny of the equilibrium potential together with its tanpera-ture coefficient was first proved in several works [9-13] published soon after. The approach to the calculation of kinetic parameters using the thermodynamic data, which is the subject of this chapter, has been proposed [14-16] later. In early 2000, new interest in the method has arisen, both in the thermodynamics of the processes within the electrodes for lithium-ion cells [17-22] and in the connection between thermodynamic functions and kinetic parameters [23]. In the series of recent works, M. Bazant [24] described the development of the fundamental theory of electrochemical kinetics and charge transfer applied to lithium iron phosphate (LFP). 

The thermodynamic data available for lithium metal and the lithium ion are listed in Table 6.3. 

Lithium-ammonia reductions of most steroidal enones of interest create one or two new asymmetric centers. Such reductions are found to be highly stereoselective and this stereoselectivity constitutes the great utility of the reaction. For conjugated enones of the normal steroid series, the thermodynamically most stable products are formed predominantly and perhaps exclusively. Thus the following configurations are favored 5a, 8/ , 9a, and in certain cases 14a (see page 35). Starr has listed numerous examples illustrating these facts and Smith " and Barton have tabulated similar data. 

A series of experiments have been undertaken to evaluate the relevant thermodynamic properties of a number of binary lithium alloy systems. The early work was directed towards determination of their behavior at about 400 °C because of interest in their potential use as components in molten salt batteries operating in that general temperature range. Data for a number of binary lithium alloy systems at about 400 °C are presented in Table 1. These were mostly obtained by the use of an experimental arrangement employing the LiCl-KCl eutectic molten salt as a lithiumconducting electrolyte. 

Polymers - The PS, PDMS, polyhexylisocyanate (PHIC), and polylso-prene (PI) samples had been extensively characterized to determine molecular weights, molecular sizes, and thermodynamic parameters (5, 6, 7 ). The samples were anionlcally polymerized using butyl lithium as the initiator. The pertinent data are shown in Table L Polylsobutylene/PIB polymers were obtained by fractionation of commercial polymers and their molecular weights were measured (8). 

Propylene Carbonate (PC) and Water. Data from both spectroscopic and thermodynamic studies for other solvent systems are sparse and some of it is of doubtful quality. For propylene carbonate, Salomon (40) has obtained emf data using lithium metal and thallium amalgam-thallous chloride or bromide electrodes. 

Na-NH3, 1.02 x 108 ohm-1 cm2 mol-1 for Hg, 0°C, 0.16 x 10 ohm-1 cm2 mol-1). In the intermediate composition range 1 to 7 MPM, a NM-M transition occurs, and changes in the electronic, thermodynamic, and mechanical properties of the system are equally impressive (35, 37, 124, 154). A detailed discussion of the concentration dependence of various properties of metal-ammonia solutions is given in the book by Thompson (164). In addition, a recent review (60) at Colloque Weyl V also summarizes the available data for lithium-methylamine solutions (10, 11, 63, 127, 128, 166). 

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