Introduction

Abstract

The book deals with the properties of single substances that are ionic and in the liquid state. The layout of the chapters: Chap. 2 shows the properties of the ions constituting ionic liquids, Chap. 3 deals with the properties of high-melting, i.e. molten salts, Chap. 4 shows some data on network, eventually glass forming, molten salts, Chap. 5 shows the properties of low-melting salts, including hydrated salts, and Chap. 6 deals with the properties of room temperature ionic liquids. Books dealing with ionic liquids are mentioned and the list of symbols and abbreviations used throughout the book is presented.

List of Symbols

Chemical species and units of physical quantities are denoted by Roman type characters, whereas physical quantities that can be expressed by numerical values are denoted by Greek or italics characters. Mathematical symbols have their usual meaning and are not listed here. The same symbol is used for an extensive property of a system and for the molar quantity of a constituent of the system. The SI systems of physical units is used throughout, but some extra-SI ones commonly used in the physicochemical literature are also included where they simplify the notation. These include the symbols °C for centigrade temperatures (T/K – 273.15).

A :

Helmholz energy, molar Helmholz energy (in J mol⁻¹)

a _X :

thermodynamic activity of species X

B(T):

Tait expression temperature-dependent parameter

B _x :

activation energy for process x (η, κ, Λ, or D)

ce :

cohesive energy (in kJ mol^–1)

ced :

cohesive energy density (in MPa)

C _P :

molar heat capacity at constant pressure (in J∙K⁻¹∙mol⁻¹)

C _v :

molar heat capacity at constant volume (in J∙K^–1∙mol^–1)

c _X :

molar concentration of species X (in M = mol∙dm⁻³)

C^z+ :

a generalized cation

D :

diffusion coefficient (in m²∙s⁻¹)

d :

interionic distance (in nm)

E :

energy, molar energy (in J∙mol⁻¹)

e :

elementary charge (1.6022 × 10⁻¹⁹ C)

E _T ^N :

normalized polarity index

F :

Faraday constant (9.6485 × 10⁴ C∙mol⁻¹)

G :

Gibbs energy, molar Gibbs energy (in J∙mol⁻¹)

g(r):

pair correlation function

GP :

Gordon parameter

H :

enthalpy, molar enthalpy (in J∙mol⁻¹)

h :

solvation (hydration) number

I :

radiation scattering intensity

I :

moment of inertia

k _B :

Boltzmann constant (1.3807 × 10^–23 J∙K⁻¹)

K _H :

Henry’s law constant

m :

number of segments

M _X :

molar mass of species X (in kg∙mol⁻¹)

N _A :

Avogadro’s number (6.0221 × 10²³ mol⁻¹)

N _co :

coordination number

n _D :

refractive index at the sodium D line

P :

pressure (in Pa)

p :

vapor pressure (in Pa)

P ^O _W :

octanol/water partition constant

P _σ :

parachor

R :

gas constant (8.3145 J∙K⁻¹∙mol⁻¹)

r _corr :

linear correlation coefficient

R _D :

molar refractivity at the sodium D line (in m³∙mol⁻¹)

r _X :

radius of particle of species X (in nm)

S :

entropy, molar entropy (in J∙K⁻¹∙mol⁻¹)

S(q):

structure factor in q (reciprocal length) space

T :

temperature (in K)

t :

transference number

U :

Potential interaction energy in the system (in J)

u :

speed of sound (in m∙s⁻¹)

u(r):

potential energy function

V :

volume, molar volume (in m³∙mol⁻¹)

v _X :

microscopic volume of species X (in nm³)

x _X :

mole fraction of species X

y :

packing fraction

Z :

lattice parameter

Z _X :

atomic number of element X

z _X :

charge number of ionic species X (taken algebraically)

Δ_x :

change of quantity for process x

α :

Kamlet-Taft hydrogen bond donation ability of solvent

α _P :

isobaric thermal expansibility (in K⁻¹)

α _X :

polarizability of species X (in m⁻³⁾

β :

Kamlet-Taft electron pair donation ability of solvent

δ :

chemical shift of NMR signal (in ppm)

δ _H :

Hildebrand solubility parameter (in MPa^1/2)

ε, ε _s,:

relative static permittivity

ε ₀ :

permittivity of empty space (8.8542 × 10⁻¹² C²∙J⁻¹∙m⁻¹)

η :

dynamic viscosity (Pa∙s)

θ _D, θ _E :

Debye or Einstein temperature

κ :

specific conductance (S∙m⁻¹)

κ _S, κ _T :

adiabatic (isentropic), isothermal compressibility (in Pa^–1)

Λ :

molar conductivity (in S∙cm²∙mol⁻¹)

λ :

wavelength of radiation

λ _th :

thermal conductivity (in W∙m⁻¹∙K⁻¹⁾

ν _I :

stoichiometric coefficient (number of ions I per formula)

π*:

Kamlet-Taft polarity/polarizability of solvent

ρ :

density (in kg∙m⁻³)

σ :

surface tension (in N∙m⁻¹)

σ _I :

softness parameter of ion I

Φ :

fluidity (reciprocal of viscosity) (in Pa⁻¹ s⁻¹)

χ :

molar (diamagnetic) susceptibility (in m³∙mol⁻¹)

ω :

frequency of an electromagnetic wave (in s⁻¹)

₊, ₋ :

of cation, anion

₀ :

of a unit quantity

₀ :

characteristic temperature in VFT equation

_b :

of boiling (at atmospheric pressure)

_c :

critical

_els :

contribution from electrostriction

_f :

of formation

_g :

of glass transition

_h :

of a hole

_hyd :

pertaining to hydration

_I :

pertaining to the ion I

_int :

internal

_intr :

intrinsic value

_{L, latt} :

of lattice

_m :

of melting

_r :

reduced quantity

_s :

of sublimation

_sd :

of solid

_solv :

of solvation

_v :

of vaporization

_vd :

of void space, of cavity

^* :

characteristic quantity

^o :

standard thermodynamic function (for T = 298.15 K, for P = 0.1 MPa)

A chemical substance or ion is generally referred to in the text by its name or formula, but in tables and as subscripts abbreviations are generally employed. The symbol I^z± denotes a generalized ion, C⁺ or M^z+ denote a cation, and A⁻ and X^z− denote an anion. The abbreviations cr for crystal, g for gas, ig for ideal gas, l for liquid denote the state of the ion or substance described. The common abbreviations of alkyl chains, Me = methyl, Et = ethyl, Pr = 1-propyl, Bu = 1-butyl, Pe = 1-pentyl, Hx = 1-hexyl, Oc = 1-octyl, Dc = 1-decyl, Do = 1-dodecyl, Td = 1-tetradecyl, and also Ph = phenyl are employed.