Structure of matter

Matter and Energy

Ø Everything is made up of particles of matter and fields of energy / force, which means that the
fundamental structural elements of the organic and inorganic world are identical.



Ø Living matter differs from non-living matter only by its much higher level of organisation.

Elementary Particles of Matter

Ø  The elementary (i.e, have no internal structure) particles of matter are leptons and quarks



Ø  Leptons – electrons, muons, neutrinos and their anti-particles – light particles without
internal structure



Ø  Quarks (u, c, t, d, s, b) – heavier particles without internal structure



Ø  Hadrons – heavy particles formed of quarks e.g., proton (u, u, d), neutron (d, d, u)



                            The Four Fundamental Energy / Force Fields

Photons

Ø Photons - energy quanta of electromagnetic field, zero mass



Ø Energy of (one) photon: E = h.f = h.c/l

h is the Planck constant (6.62 x 10^-34 J.s),

f  is the frequency,

c is speed of light in vacuum

l is the wavelength

Particles and Field Energy Quanta

particles of matter and field energy quanta are capable of mutual transformation (e.g., an
electron-positron pair transform to two gamma photons – this is used in PET imaging)



Quantum Mechanics

The behaviors of ensembles of a given type of particle obey equations which are similar to wave
equations.

Quantum Mechanics
tunnel effect:

Quantum Mechanics: Heisenberg uncertainty relations

                                           dr.dp ≥ h/2p

                                           dE.dt ≥ h/2p



The position r and momentum p of a particle cannot be simultaneously measured with independent
precision (if the uncertainty of particle position – dr – is made smaller, the uncertainty of
particle momentum – dp – automatically increases). The same holds for the simultaneous measurement
of energy change dE and the time dt necessary for this change.

Schrödinger equation
(to admire)

Solution of the Schrödinger Equation

Ø  The solution of the Schrödinger equation for the electron in the hydrogen atom leads to the
values of the energies of the orbital electron.



Ø  The solution of the Schrödinger equation often leads to numerical coefficients which determine
the possible values of energy. These numerical coefficients are called quantum numbers

Quantum numbers for Hydrogen

Ø Principal  n = 1, 2, 3 …. (K, L, M, ….)

Ø Orbital for each n   l = 0, 1, 2, …. n – 1 (s, p, d, f …)

Ø Magnetic for each l     m = 0, ±1, ±2, …±l

Ø Spin magnetic for each m  s = ±1/2





Ø Pauli exclusion principle – in one atomic electron shell there cannot be present two or more
electrons with the same set of quantum numbers.

Ionisation of Atoms

Emission Spectra

Hydrogen spectrum again
magenta, cyan and red line
according
http://cwx.prenhall.com/bookbind/pubbooks/hillchem3/medialib/media_portfolio/text_images/CH07/FG07_
19.JPG

Excitation (absorption) Spectra for Atoms

Excitation (Absorption) Spectrum for Molecules

Atom nucleus

Mass defect of nucleus

= measure of nucleus stability:

                                   dm = (Z.m[p] + N.m[n]) - m[j]

Nuclides

Ø nuclide - a nucleus with a given A, Z and energy



Ø Isotopes - nuclides with same Z but different A



Ø Isobars – nuclides with same A but different Z



Ø Isomers – nuclides with same Z and A, but different energy (e.g., Tc^99m used in gamma camera
imaging)

Isotope composition of mercury
% of atoms vs. isotope nucleon number

What else is necessary to know?

Ø Radionuclides – nuclides capable of radioactive decay





Ø Nuclear spin:

    Nuclei have a property called spin. If the value of the spin is not zero the nuclei have a
magnetic moment i.e, they behave like small magnets - NMR – nuclear magnetic resonance spectroscopy
and magnetic resonance imaging in radiology are based on this property.

Author:
Vojtěch Mornstein
Content collaboration and language revision:
Carmel J. Caruana
Presentation design:
Lucie Mornsteinová
Last revision: March 2008