Paramagnetism and Diamagnetism - Department of Chemistry

1 1 Paramagnetism and DiamagnetismzAtoms with unpaired electrons are called paramagnetic. Paramagnetic atoms are attracted to a with paired electrons are called diamagneticdiamagnetic. Diamagnetic atoms are repelled by a number of orbitals per n level is given by maximum number of electrons per n level is Level# of OrbitalsMax. # of e-nnnn222n2 11 224 83918416 324 The Periodic Table and Electron ConfigurationszThe principle that describes how the periodic chart is a function of electronic configurations is the Aufbau electron that distinguishes an element from the previous element enters the lowest energy atomic orbital Periodic Table and Electron ConfigurationszThe Aufbau Principle describes the electron filling order in Hund s ruletells us that the electrons will fill the p orbitals by placing electrons in each orbital singly and with same spin until half-filled. Then the electrons will pair to finish the p s rule8 The Periodic Table and Electron Configurationsz1strow elements22111s He1s H ionConfigurat 1s 111s HionConfigurat 1s 9z2ndrow elements62210522942283227222612252241232 p 2s 1s Ne2p 2s 1s F2p 2s 1s O2p 2s 1s N2p 2s 1s C2p 2s 1s B2s 1s Be2s 1s LiionConfigurat 2p 2s 1s 10z3rdrow elements[][][][][][][][][][][][][][][][]

2 6218521742163215221412132121113p s3 Ne NeAr 3p s3 Ne Ne Cl3p s3 Ne Ne S3p s3 Ne Ne P3p s3 Ne Ne Si3p s3 Ne Ne Als3 Ne Ne Mgs3 Ne Ne NaionConfigurat 3p 3s 11[][][][][][][][][][][][] 3d 4s Ar ArCr 3d 4s Ar Ar V3d 4s Ar Ar Ti3d 4s Ar Ar Sc4s Ar Ar Ca4s Ar ArK ionConfigurat 4p 4s 3d 5124322322221221220119 There is an extra measure of stability associated with half-filled or completely filled Periodic Table and Electron Configurations[][][][][][][][][][][][]

3 102301012982287227622652253d 4s Ar Ar Zn3d 4s Ar Ar Cu3d 4s Ar Ar Ni3d 4s Ar Ar Co3d 4s Ar Ar Fe3d 4s Ar Ar MnionConfigurat 4p 4s 3d 13 The Periodic Table and Electron Configurations[][][][][][][][][][][][]61 02365102354102343102332102321102314p 3d 4s Ar ArKr 4p 3d 4s Ar ArBr 4p 3d 4s Ar Ar Se4p 3d 4s Ar Ar As4p 3d 4s Ar Ar Ge4p 3d 4s Ar Ar GaionConfigurat 4p 4s 3d 14 The Periodic Table and Electron ConfigurationszNow we can write a complete set of quantum numbers for all of the electrons in these three elements as examples.

4 Na Ca Fe15}electron s 31/2 0 0 3 e 11electrons p 21/2 1 1 2 e 101/2 0 1 2 e 9 1/2 1 1 2 e 8 1/2 1 1 2 e 7 1/2 0 1 2 e 6 1/2 1- 1 2 e 5 electrons s 21/2 0 0 2 e 4 1/2 0 0 2 e 3 electrons s 11/2 0 0 1 e 2 1/2 0 0 1 e 1 m m n -th-th-th-th-th-th-th-th-rd-nd-sts+ + ++++ + +ll[][]111s3 Ne NeNa ionConfigurat 3p 3s 16[]2204s Ar [Ar]Ca ionConfigurat 4p 4s 3d electrons s 41/2 0 0 4 e 20 1/2 0 0 4 e 19]Ar[m m n -th-ths +ll17[][]62263d 4s Ar Ar FeionConfigurat 4p 4s 3d 1/2 2- 2 3 e 26 1/2 2 2 3 e 25 1/2 1 2 3 e 24 1/2 0 2 3 e 23 1/2 1- 2 3 e 22 1/2 2- 2 3 e 21 electrons s 41/2 0 0 4 e 20 1/2 0 0 4 e 19 [Ar]m m n -th-th-th-rd-nd-st-th-ths +++++++ +ll