Glossary of Common Symbols
Common Mathematical Symbols (excluding symbols of calculus)
=
( and ≠ )
equal to (not equal to)
≈
~
( or ≅ )
approximately equal to
"of the order of " (less precise than ~ )
=ˆ
( and ≡ )
identical to (equivalent to)
( and < )
proportional to (i.e. equal to a constant times ..)
infinity (an extremely large value)
greater than (less than)
∝
∞
>
≥ ( and ≤ )
>> ( and << )
greater than or equal to (less than or equal to)
very much greater than (very much less than)
x
average value of x
⟨x⟩
expectation value of x (similar to average)
|x |
modulus (absolute value) of x
⇒ (or ∴ )
"leads to" / "therefore" / "hence" (i.e. next line of a logical argument)
Common Greek Symbols and their Chemical / Mathematical associations
The following list is not the full Greek alphabet: less commonly used characters from have been
omitted. Not all associations have been mentioned. Upper case symbols are only shown if they are
commonly used. The characters will be italicized when used as symbols for physical quantities.
Lower
Case
α
β
χ
δ
ε
φ
γ
η
κ
λ
µ
ν
π
θ
ρ
σ
τ
ω
ψ
Upper
Case
∆
Φ
Γ
Λ
Π
Σ
Ω
Ψ
Name
Common Associations / Uses
alpha
beta
chi
delta
epsilon
phi
gamma
eta
kappa
lambda
mu
nu
pi
theta
rho
sigma
tau
omega
psi
α - Coulomb integral
β - Resonance integral
χ - magnetic susceptibility
δ - small change, chemical shift: ∆ - large change
ε - molar absorption coefficient, dielectric constant
φ - atomic wavefunction, azimuthal angle
γ - surface tension, activity coefficient
η - viscosity
κ - thermal and electrical conductivity
λ - wavelength : Λ - molar conductivity
µ - chemical potential, reduced mass, dipole moment
ν - frequency
π = 3.14159.... : Π - product, osmotic pressure
θ - an angle, temperature, surface coverage
ρ - density
σ - collision cross-section; Σ - summation.
τ - period, time constant, lifetime
ω - angular frequency
ψ , Ψ - wavefunctions