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IUPAC Compendium of Chemical Terminology

 

[A] [B] [C] [D] [E] [F] [G] [H] [I] [J] [K] [L] [M]
[N] [O] [P] [Q] [R] [S] [T] [U] [V] [W] [X] [Y] [Z]

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pi-sigma* transition
sigma, pi
sigma-sigma* transition
S
saccharides
Sackur-Tetrode constant
sacrificial acceptor
sacrificial donor
sacrificial hyperconjugation
saddle point
salt
salt effect
salt form of an ion exchanger
salting out
sample (in analytical chemistry)
sample error (in spectrochemical analysis)
sample handling (in analysis)
sample injector (in chromatography)
sampler
sample unit
sampling error
sampling interval (in electroanalysis)
sampling plan (in analytical chemistry)
sampling time (in electroanalysis)
sandwich compounds
sanitary land fill
saprophyte
saturated solution
saturation
saturation (in radioanalytical chemistry)
saturation activity
saturation capacity
saturation fraction
saturation loading
saturation transfer
saturation vapour pressure
sawhorse projection
Saytzeff rule
sc
scaler
scaling circuit
scaling factor
scanning electron microscopy (SEM)
scanning method (in mass spectrometry)
scanning transmission electron microscopy (STEM)
scattering
scattering angle, theta
scattering cross-section
scattering error (in spectrochemical analysis)
scattering matrix
scattering plane
scattering vector
scavenger
scavenging
Schenck sensitization mechanism
Schiff bases (Schiff's bases)
Schiller layers
Schottky-barrier photodiode
Schulze-Hardy rule
Schulz-Zimm distribution
scintillation
scintillation counter
scintillation detector
scintillation spectrometer
scintillators
s-cis, s-trans
scrambling
scrubber (in atmospheric chemistry)
scrubbing
seco-
second
second messenger
second (of arc)
secondary crystallization
secondary current distribution
secondary electron multiplier (in mass spectrometry)
secondary electrons (se) (in in situ microanalysis)
secondary electron yield (in in situ microanalysis)
secondary excitation (of X-rays)
secondary fluorescence (in X-ray emission spectroscopy)
secondary ionization (in mass spectrometry)
secondary isotope effect
secondary kinetic electrolyte effect
secondary kinetic isotope effect
secondary metabolites
secondary pollution (emissions)
secondary radiation
secondary standard
secondary structure
second-order transition
secular equation
secular equilibrium
sediment
sedimentation
sedimentation coefficient, s
sedimentation equilibrium
sedimentation field strength
sedimentation potential difference (sedimentation potential)
sedimentation velocity
sedimentation velocity method
sedimentation volume
segment (in analytical chemistry)
segmented copolymer
segregated star macromolecule
segregation
segregation (in polymers)
selected area electron diffraction (SAED)
selected ion monitoring (in mass spectrometry)
selection (in biotechnology)
selection rule
selective (in analysis)
selective corrosion
selective detector
selective digestion (in spectrochemical analysis)
selective elution (in chromatography)
selective inhibition (in catalysis)
selectively labelled
selective micro-sample (in spectrochemical analysis)
selective poisoning (in catalysis)
selective preconcentration (in trace analysis)
selective sample
selective solvent (in polymer chemistry)
selective sorption (in polymer chemistry)
selectivity
selectivity (in analysis)
selectivity (of a reagent)
selectivity coefficient (in ion exchange chromatography), kA/B
selectivity factor
selectivity factor (in ion exchange chromatography)
selectivity ratio
selenenic acids
selenides
seleninic acids
selenocyanates
selenols
selenones
selenonic acids
selenoxides
self-absorption
self-absorption broadening (of a spectral line)
self-absorption effect (in luminescence spectroscopy)
self-absorption factor (of a radiation source)
self-diffusion coefficient
self inductance, L
self-poisoning (in catalysis)
self-quenching
self-reversal
self-shielding
selones
semicarbazones
semicoke
semiconductor
semiconductor detector
semiconductor laser
semiconductor-metal transition
semi-empirical quantum mechanical methods
semi-interpenetrating polymer network (SIPN) 1996, 68, 2305
semi-interpenetrating polymer network 2004, 76, 1989 (This supersedes an earlier definition)
semioxamazones
semiquinones
semi-rigid chain
semisystematic name (semitrivial name)
seniority (senior)(in organic nomenclature)
sensitive area (of a radiation detector)
sensitive volume (of a radiation detector)
sensitivity (in mass spectrometry)
sensitivity (in metrology and analytical chemistry), A
sensitization
sensitization (in colloid chemistry)
sensitized luminescence
sensitizer
separability assumption
separated flame (in flame spectroscopy)
separation coefficient
separation factor (in column chromatography),
separation factor (in liquid-liquid distribution),
separation number (in chromatography), SNHeader=separation number (in chromatography), SN
separation temperature (in chromatography)
sequence
sequence rules
sequencing (proteins, nucleic acids)
sequential analyser
sequential indication (of an analyser)
sequential measuring cell
sequential sample
sequential spectrometer
series (of analytical results)
serum
sesquiterpenoids
sesterterpenoids
settling chamber (in atmospheric chemistry)
settling error (in spectrochemical analysis)
settling velocity
shape-memory polymer
shape selectivity (in catalysis)
shear breakdown
shear dependent viscosity
shear modulus, G
shear rate
shear strain, gamma
shear stress, tau
shear thickening
shear thinning
shear transition
shear viscosity
shielded flame (in flame spectroscopy)
shielding
shielding constant, sigma
shish-kebab structure
short chain
short-chain branch
short-range intramolecular interactions (in polymers)
shut-down state (in analysis)
shut-down time (in analysis)
shuttle vector
SI
Si
sialon
side chain
side group
side-group or side-chain polymer liquid-crystal
siemens
sievert
sigmatropic rearrangement
signal (in analysis)
signal sequence
silanes
silanols
silasesquiazanes
silasesquioxanes
silasesquithianes
silathianes
silazanes
silicones
siloxanes
silver film
silylene
silyl groups
silyl radicals
simple shear
simulation technique (in analysis)
simultaneous nucleation
simultaneous pair transitions
simultaneous reactions
simultaneous spectrometer
single-beam (luminescence) spectrometer
single cell protein (SCP)
single channel pulse height analyser
single-electron transfer mechanism (SET)
single escape peak
single-focusing mass spectrometer
single photon counting
single photon timing
single scattering
single-step reaction
single-strand chain (in a polymer)
single-strand macromolecule
single-strand polymer
singlet molecular oxygen
singlet-singlet absorption
singlet-singlet annihilation
singlet-singlet energy transfer
singlet state
singlet-triplet absorption
singlet-triplet energy transfer
singly labelled
sink (in atmospheric chemistry)
sintering
size-exclusion chromatography (SEC)
skeletal atom
skeletal bond
skeletal structure
skew
Slater determinant
Slater-type orbital
slot burner
slow neutrons
small particle (in radiation scattering)
smectic state
SMILES
SM-interference
smog (in atmospheric chemistry)
smog chamber (in atmospheric chemistry)
smog index (in atmospheric chemistry)
smoke
smooth transition
soap
soap curd
soap film
soft acid
soft base
soft-segment phase domain
soiling (in atmospheric chemistry)
sol
solar conversion efficiency
solar flare
solar radiation (in atmospheric chemistry)
sol-gel process
sol-gel transition
solid angle, omega
solidification
solid phase antibody radioimmunoassay
solid polymer electrolyte
solid solution
solid state lasers
solid support (in column chromatography)
solidus
solid volume (in column chromatography)
soliton
solubility
solubility parameter (of a polymer),
solubility product
solubilization
solute
solute-volatilization interference (in flame spectroscopy)
solution
solvation
solvation energy
solvatochromic relationship
solvatochromism
solvent
solvent (in liquid-liquid distribution)
solvent extraction
solvent front (in chromatography)
solvent ion exchange (SIX)
solvent isotope effect
solvent migration-distance (in chromatography)
solvent parameter
solvent regeneration (in extraction processes)
solvent-separated ion pair
solvent-shared ion pair
solvent shift
solvolysis
solvophobicity parameter
solvus
SOMO
sonication
sonoluminescence
soot
redox polymers
soret band
sorption isotherm (in ion exchange)
sorption techniques (in trace analysis)
sorptive insertion (in surface catalysis)
source efficiency (of a radiation source)
sp
space charge (in a semiconductor)
space formula
space time (in catalysis)
space velocity (in catalysis)
spacer
spark (source) ionization (in mass spectrometry)
spatial-distribution interference (in flame spectroscopy)
spatially resolving detector (of radiation)
special salt effect
speciation
speciation (in chemistry)
speciation analysis (in chemistry)
species (taxonomic)
specific
specific (in analysis)
specific acid-base catalysis
specific activity (in radiochemistry), a
specific adsorption
specifically absorbing ion
specifically labelled
specifically labelled tracer
specific burn-up
specific catalysis
specific conductance
specific detector (in chromatography)
specific gravity
specific heat capacity, c
specific ionization (in nuclear chemistry)
specific permeability (in chromatography)
specific photon emission
specific pore volume (of a catalyst)
specific retention volume (in chromatography)
specific surface area (in surface chemistry)
specific volume, v
specific weight
specimen (in analytical chemistry)
spectator mechanism
spectator-stripping reaction
spectral bandwidth error (in spectrochemical analysis)
spectral distribution
spectral (photon) effectiveness
spectral intensity
spectral interference (in flame spectroscopy)
spectral irradiance
spectral overlap
spectral photon exitance
spectral photon flow
spectral photon flux (photon irradiance)
spectral photon radiance
spectral quantities
spectral radiance
spectral radiant excitance
spectral radiant flux
spectral radiant intensity
spectral radiant power
spectral responsivity
spectral responsivity function
spectral sensitization
spectral spheradiance
spectrochemical buffer (in atomic spectroscopy)
spectrochemical carrier (in atomic spectroscopy)
spectrogram
spectrograph
spectrometer
spectrometry
spectroscope
spectroscopy
spectrum analysis
specular reflectance (reflection factor) (in optical spectroscopy),
speed, v, c
speed distribution function, F(c)
speed of light in a vacuum
spherical carbonaceous mesophase
spherical radiance
spherical radiant exposure
spherulite
spin adduct
spin-allowed electronic transition
spin contamination
spin conservation rule (Wigner rule)
spin counting
spin crossover
spin density
spin-flip transition
spin-flop transition
spin-glass transition
spin label
spinodal curve
spinodal decomposition
spin-orbit coupling
spin-orbit coupling constant, A
spin-orbit splitting
spin-Peierls transition
spin polarization
spin probe
spin projection
spin-spin coupling
spin-spin coupling constant
spin-state transition
spin trapping
spiro atom
spiro chain (in a polymer)
spiro compounds
spiro macromolecule
spiro polymer
spiro union
splicing
spontaneous emission
spontaneous fission
spontaneous resolution
spot (in chromatography)
spot sampling
sprayer (in flame spectroscopy)
spreading function (in chromatography)
spreading wetting
spread monolayer
sputtering
sputter yield
square-wave current
SR
stable
stability constant
stable film, metastable film
stable ion (in mass spectrometry)
staggered conformation
stagnant inversion (in atmospheric chemistry)
standard acceleration of free fall
standard atmosphere
standard atomic weights
standard chemical potential
standard concentration
standard conditions for gases
standard deviation, s
standard electrode potential
standard electromotive force
standard entropy of activation
standard equilibrium constant
standard Gibbs energy of activation
standard hydrogen electrode
standard molality
standard potential of an electrode reaction
standard potential of the reaction in a chemical cell
standard pressure
standard rate constant of an electrode reaction
standard reaction quantities
standard solution
standard state
standard subtraction method (in electroanalytical chemistry)
standard thermodynamic quantities
standard uncertainty
stand-by state (in analysis)
stannoxanes
stannylenes
stannylidenes
star copolymer
Stark effect
star macromolecule
star polymer
starting line (in chromatography)
starting point (in chromatography)
start-up time (in analysis)
state crossing
state diagram
state function
state-to-state kinetics
static fields mass spectrometer
static pressure
static quenching
static stability
stationary phase (fermentation)
stationary phase (in chromatography)
stationary-phase fraction
stationary phase volume (in chromatography), Vs
stationary state
statistical coil (in polymers)
statistical copolymer
statistical copolymerization
statistical factor
statistical pseudo-copolymer
statistical segment (in polymers)
statistical weight
steady state (in liquid-liquid distribution)
steady state (stationary state)
steady state approximation (treatment)
Stefan-Boltzmann constant
stem (in polymer crystals)
stem cell
step (in chromatography)
step height (in chromatography)
stepped surface
stepwise elution (in chromatography)
stepwise reaction
steradian
stereoblock macromolecule
stereoblock polymer
stereochemical formula (stereoformula)
stereochemical non-rigidity
stereoconvergence
stereodescriptor
stereoelectronic
stereoelectronic control
stereoformula
stereogenic unit (stereogen/stereoelement)
stereoheterotopic
stereohomosequence (in a polymer)
stereoisomerism
stereoisomers
stereomutation
stereoregular macromolecule
stereoregular polymer
stereorepeating unit (in a polymer)
stereoselective polymerization
stereoselective synthesis
stereoselectivity
stereosequence (in a polymer)
stereospecifically labelled tracer
stereospecificity (stereospecific)
stereospecific polymerization
steric-approach control
steric effect
steric factor
steric factor (in polymers)
steric hindrance
steric isotope effect
steric strain
Stern layer
Stern-Volmer kinetic relationships
steroids
sterols
stibanes
stibanylidenes
stibines
stibinidenes
stibonium compounds
sticking coefficient (in surface chemistry)
sticking probability (in surface chemistry)
sticky ends (in biotechnology)
stimulated emission
stirred flow reactor (in catalysis)
stochastic effect
stochastic sampling
stochastic theories
Stockholm convention
Stock number
stoichiometric
stoichiometric capacity
stoichiometric concentration, c
stoichiometric mean molal (practical) activity coefficient (in electrochemistry)
stoichiometric number, nu
stoichiometry
stokes
Stokes law
Stokes number, St
Stokes parameters
Stokes shift
Stokes type radiation
stopped flow
stopped-flow cell (in spectrochemical analysis)
stopping power
STP
strain
strain energy
strain-induced transition
stratified film
stratified sample
stratocumulus cloud
stratopause
stratosphere
stratus cloud
stray radiation error (in spectrochemical analysis)
streak camera
streak tube
streaming birefringence
streaming current
streaming potential difference (streaming potential)
stress-assisted transition
stress graphitization
strip dynode photomultiplier tube
stripping
stripping isotherm
stripping ratio (in solvent extraction)
stripping reaction
stripping solution (in liquid-liquid distribution)
strong collision
structural disorder
structural formula
structural stability
structural transition
structure (of a catalyst)
structure-activity relationship, SAR
structure-based design (in drug design)
structure-property correlations (SPC)
styphnates
subchain (of a polymer)
subgroup-supergroup transition
subjacent orbital
sublation (in solvent extraction)
sublimation
subphase (in thin films)
subsample
substance concentration
substance content
substance flow rate
substance fraction, x
substituent atom (group)
substituent electronegativity
substitution reaction
substitutive name
substoichiometric extraction
substoichiometric isotope dilution analysis
substrate
substrate (in biocatalysis)
substrate (in thin films)
subtractive name
successor complex
sudden polarization
sudden potential-energy surface
sugars
suicide inhibition
suicide metabolism
sulfamic acids
sulfanes
sulfatides
sulfenamides
sulfenes
sulfenic acids
sulfenium ions
sulfenyl groups
sulfenylium ions
sulfenyl nitrenes
sulfenyl radicals
sulfides
sulfilimines
sulfimides
sulfimines
sulfinamides
sulfinamidines
sulfines
sulfinic acids
sulfinic anhydrides
sulfinimines
sulfinylamines
sulfolipids
sulfonamides
sulfonamidines
sulfonediimines
sulfones
sulfonic acids
sulfonic anhydrides
sulfonimides
sulfonium compounds
sulfonphthaleins
sulfonylamines
sulfoxides
sulfoximides
sulfoximines
sulfur diimides
sultams
sultims
sultines
sultones
summit current (in polarography)
summit potential
sum of states
superabsorbent polymer
superacid
superbase
superconducting transition
supercritical fluid
supercritical fluid chromatography (SFC)
superequivalent adsorption
superexchange interaction
superficial work (in surface chemistry)
superlattice
superposability
superradiance
supersaturation
support (of a catalyst)
support-coated open-tubular (SCOT) column (in chromatography)
supporting electrolyte
support plate (in chromatography)
suppressor
suprafacial
supramolecular chemistry
supramolecule
surface
surface active agent
surface amount
surface barrier semiconductor detector
surface catalysis
surface charge density, sigma
surface charge layer
surface chemical potential
surface concentration, gamma
surface (excess) conductivity
surface contamination (in surface analysis)
surface coverage, theta
surface crossing
surface density
surface dilatational viscosity
surface dipole layer
surface electric potential
surface excess
surface excess concentration (at an interface),
surface excess energy
surface excess enthalpy
surface excess entropy
surface excess Gibbs energy
surface excess Helmholtz energy
surface excess isotherm
surface grafting
surface ionization (in mass spectrometry)
surface ions
surface layer (or interfacial layer)
surface of a phase (free surface)
surface of tension
surface potential
surface pressure
surface reaction (in electrochemistry)
surface region
surface rheology
surface shear viscosity
surface states
surface stress
surface tension, gamma, sigma
surface work
surfactant (surface active agent)
surprisal, s
surprisal analysis
suspended matter (in atmospheric chemistry)
suspension
suspension effect (in an ion-selective electrode)
Swain-Lupton equation
Swain-Scott equation
swelling (in colloid and surface chemistry)
swelling pressure (in colloid and surface chemistry)
switchboard model (in polymer crystals)
switching transition
sydnone imines
sydnones
sym-
symbiosis
symbol (in quantities and units)
symmetrical films
symmetry-breaking transition
symmetry-conserving transition
symmetry number, s
symproportionation
syn
synartetic acceleration
synchronization (principle of nonperfect synchronization)
synchronous
synchronously excited (fluorescence, phosphorescence) spectrum
synchrotron radiation
synclinal
syndet
syndiotactic macromolecule
syndiotactic polymer
syndiotactic triads (in polymers)
syneresis
synergism (in solvent extraction)
synergism (in toxicology)
synoptic scale
synperiplanar
syntectic reaction
synthetic graphite
system
systematic error
systematic name
system of units (of measurement)
systemic effect
Systeme International d'Unites
Szilard-Chalmers effect


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