4448 PCHEM TERMS - Atomic Spectroscopy

Balmer series

a series of spectral lines that appear in the visible region for a hydrogen atom when it undergoes transitions from n>2 to n=2, Atkins' Physical Chemistry 11th Edition pg 304 entered by Patricia Hernandez, edited by DW

Hydrogenic Atom

An atom that has all but one electron removed so that (like hydrogen) it only has a nucleus and one electron. entered by DW

Net spin

The spin of an atom that results from the sum of the spins of the electrons regardless of what orbitals the electrons are in. It is given the symbol s (lower case). entered by DW

Principal quantum number

Symbol n, (n=1,2,3...) specifies the energy of the orbital and tells you what shell the electron is in

Atkins' Physical Chemistry 11th Edition Page 308 entered by Megan Mann

Angular momentum quantum number

Symbol l, (l=0,1,2,3... n-1) specifies the magnitude of the angular momentum of the electron and describes the shape of the orbital (0=s, 1=p, 2=d, 3=f... etc) Atkins' Physical Chemistry 11th Edition Page 308 entered by Megan Mann

Magnetic quantum number

Symbol m subscript l, describes the relative position of each orbital, with m_l = 0, ±1, ±2,..., ±l.

Atkins' Physical Chemistry 11th Edition Page 308 entered by Megan Mann

Electron spin quantum number

Symbol s, (or m_s) the spin magnetic quantum number "spin up" (+½) or "spin down"(-½)

Atkins' Physical Chemistry 11th Edition Page 318 entered by Megan Mann

Pauli Exclusion Principle

No two electrons can have the same four quantum numbers Notes from slides entered by Megan Mann

Angular node

the positions at which the wave function passes through zero. In spherical coordinates (r, theta, and phi) these ____ are along the theta and phi coordinates. Atkins' Physical Chemistry 11th Edition Page 287 entered by Megan Mann, edited by DW

Radial node

is spherical in shape and is when the radial wavefunction passes through zero in the r dimension. Atkins' Physical Chemistry 11th Edition Page 307 entered by Megan Mann

Aufbau filling scheme

The lowest energy electronic structure of an atom is built from the bottom up (i.e. 1s first, then 2s, etc). Atkins' Physical Chemistry 11th Edition Page 321 entered by Megan Mann

Radial Wavefunction

R(r) The radial component for the wavefunction for potential energy, V, Atkins' Physical Chemistry 11th Edition pg 305 entered by Patricia Hernandez

Multiplicity

The _____ of an atom is the resulting value from the equation 2s+1. The superscript on the term symbol is the ____. Atkins' Physical Chemistry 11th Edition Page 322-323 entered by Megan Mann

Lyman series

A series of spectral lines in the UV region for a hydrogen atom when it undergoes transitions from n>1 to n=1, Atkins' Physical Chemistry 11th Edition pg 304 entered by Patricia Hernandez, edited by DW

Paschen series

A series of spectral lines that appear in the near-IR region for a hydrogen atom when it undergoes transitions from n>3 n=3, Atkins' Physical Chemistry 11th Edition pg 304 entered by Patricia Hernandez, edited by DW

Hubble constant

H = 70.4(±1.4)(km/s)/Mpc

value (H) used to calculate the rate at which the universe is expanding; measured in kilometers per second per megaparsec

Lecture notes entered by Kyle Brennan

Parsec

pc is 3.26 light years

Lecture notes entered by Kyle Brennan

Grotrian Diagram

summarizes the energies of the states and the transitions between them for the whole atom, where delta-n is unrestricted and delta-l is ±1. Atkins' Physical Chemistry 11th Edition Page 328 entered by Kyle Brennan edited by Megan Mann with notes from slides

spin-orbit coupling

The interaction of the spin magnetic moment with the magnetic field arising from the orbital angular momentum. Atkins' Physical Chemistry 11th Edition Page 329 entered by Kyle Brennan

first ionization energy

This is the energy required to remove a single electron from a neutral atom or molecule. E1 = E(Cation) - E(Neutral) Atkins' Physical Chemistry 11th Edition Page 309 entered by Phillip Paik

Coulomb potential energy equation

V(r) = -Ze^2/4πεr

Atkins' Physical Chemistry 11th Edition Page 304 entered by Kyle Brennan

Total Spin Quantum Number, S

This set describes the coupling of electron spin. S = {s1+s2, s1+s2-1, ..., |s1-s2|}. Atkins' Physical Chemistry 11th Edition Page 332 entered by Phillip Paik, edited by DW

Hubble's Law

Hubble's law defines the proportionality between the proper distance between a galaxy and the observer, and the recessional velocity, in the equation v = Hd, where H is Hubble's constant. The recessional velocity is a measure of the distance an interstellar object is with respect to the added velocity from the expansion of space. From lecture notes, entered by Ryan Phillips

Clebsch-Gordan Series

The mathematical set that determines the max and min of coupled angular momenta. For example, L = { l(1)+l(2), l(1)+l(2)-1,... | l(1)-l(2) | }. This is used to find the L, S, and J numbers for atomic term symbols. Atkins' Physical Chemistry 11th Edition Page 332 entered by Ryan Phillips, edited by Megan Mann with notes from the L23 slides, edited by DW

Electron Configuration

According to the building-up principle, electrons occupy the available molecular orbitals so as to achieve the lowest total energy subject to the Pauli exclusion principle.

Atkins' Physical Chemistry 11th Edition Page 363 entered by Ryan Phillips

Singlet multiplicity

No unpaired electrons where 2S+1= 1

Atkins' Physical Chemistry 11th Edition Page 333 entered by Megan Mann, edited by DW

Doublet multiplicity

One unpaired electron where 2S+1=2, Atkins' Physical Chemistry 11th Edition Page 334 entered by Megan Mann, edited by DW

Triplet multiplicity

Two unpaired (parallel spin) electrons creating the net spin of s= 1, so 2(S) + 1 = 3. Atkins' Physical Chemistry 11th Edition Page 334 entered by Megan Mann, edited by DW

term symbol

specifies the angular momentum states of an atom

Atkins' Physical Chemistry 11th Edition Pg. 336 entered by Marrisa Martinez

atomic orbital

a wavefunction for an electron in an atom.

Atkins' Physical Chemistry 11th Edition Pg. 314 entered by Marrisa Martinez

s Orbitals

spherically symmetrical orbitals with no angular nodes

Atkins' Physical Chemistry 11th Edition Pg. 315 entered by Marrisa Martinez

p Orbitals

there are three _______ in a given subshell; each one has one angular node

Atkins' Physical Chemistry 11th Edition Pg. 315 entered by Marrisa Martinez

d Orbitals

there are five _____ in a given subshell; each one has two angular nodes

Atkins' Physical Chemistry 11th Edition Pg. 315 entered by Marrisa Martinez

radial distribution function

the probability density for the distribution of the electrons as a function of distance from the nucleus.

Atkins' Physical Chemistry 11th Edition Pg. 315 entered by Breanna Nelson

ionization energy (of an element)

the minimum energy required to remove an electron from the ground state of one of its atoms.

Atkins' Physical Chemistry 11th Edition Pg. 314 entered by Breanna Nelson

Isoelectronic

having the same number of electrons or the same electron configuration as another element. From Electron Configuration class notes, entered by Taylor Shelley

Atomic Term Symbol

A symbol that specifies the electron configuration of an element with the form (superscript (2S+1))L(subscript )J, where S is the total spin angular momentum, L is the total orbital angular momentum, and J is the total angular momentum (spin-orbit coupling).

From 1.6 Term Symbols http://www.chemistry.uoguelph.ca, entered by Taylor Shelley Edited by Megan Mann with notes from slides

Hund's Rule

When creating the lowest energy electronic structure for an atom, electrons occupy different orbitals of a given subshell before doubly occupying any one of them. In other words, high-spin arrangements are lower in energy than low-spin arrangements. Entered by DW.