B) A salt containing a cationic octahedral Pt(IV) complex. When dissolved in a silver nitrate solution a ppt of AgBr is obtained.

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1 CHEM 3030 ASSIGNMENT # 1 Chelates, nomenclature, VBT, CFT Chapter 25 of Petrucci is a prerequisite. 1.Using as many of the following ligands as possible (GLY, OX, DIEN, TRIEN, ACAC, BIPY, water, and bromide ion) construct the complexes described below. No other ligands may be used. Name each compound and draw a clear structure of any isomer. You must show all atoms (including hydrogens) with proper stereochemistry. (Loops or other crudities are not allowed). All chelates must be fully chelated. (ABBREV Glycinate, oxalate, diethylenetriamine, triethylenetetraamine, acetylacetone, 2,2-bipyridine) A) a neutral octahedral Co(III) complex containing a tridentate ligand. B) A salt containing a cationic octahedral Pt(IV) complex. When dissolved in a silver nitrate solution a ppt of AgBr is obtained. C) A potassium salt of an anionic octahedral Cr(III) complex. D) A tetrahedral neutral Zn complex which has optical isomers but no geometric isomers. E) A salt containing square planar Pt(II) as both the cation and anion. 2. Describe the bonding and magnetism for each of the above complexes in terms of VBT, CFT, and MOT. 3 A) List the one or two most common oxidation states in aqueous solution and give the number of d electrons for each. Ti V Cr Mn Fe Co Ni Cu Zn Sn Ag Hg Cd Al Pt B) Deja-Vu. List 20 complexes of the ions above which you actually saw in the CHEM 2030 lab; name each and give the magnetic moment in Bohr magnetons. (See Sorum and Lagowski if needed.) For example the pink Co(H 2 O) 6 2+ and the blue NiCl Write the formula and name the substance or ion present in the confirmatory test for each. Example AgCl, Ni(DMGH) 2 etc. 4. Learn the basics of organic nomenclature and use it to draw the ligands below. a) 1,4,8,11-tetraaza 2,3,9,10 tetramethylcyclotetradeca1,3,8,10 tetra-ene b) 4,7,13,16,21,24-hexa-oxa-1,10-diazabicyclo[8.8.8]hexacosane aka Crypt c) 1,4,7-trimethyl-1,4,7-triazacyclononane 5. Draw Lewis structures to discern geometry and identify lone pairs on these ligands. a) thiocyanate binds through N or S. Does this alter the geometry? b) NO - 2 can be N bonded (nitro) or O bonded (nitrite). - c) dialkyldithiocarbamates S 2 CNR 2 bind through what? denticity? d) show resonance structures for 2,4-pentanedionate ion. e) cyclam is a tetradentate N donor ligand in a 14-membered ring C 10 H 24 N 4 Draw it and contrast its geometry with 4a above. Give its IUPAC name. f) The ligand L = bis(trimethylsilyl)amide favors 3 coordination. ML 3 Why? g) Imidazole is an aromatic nitrogen heterocycle (C 3 H 4 N 2 ) found in histidine. Which nitrogen is the stronger base /better ligand and why? Draw the Lewis structure. HINT : Which N lone pairs are in p orbitals and which in an sp 2 hybrid? Identify the 6π electrons (Huckel 4n+2 rule).

2 CHEM 3030 ASSIGNMENT # 2 NAME 1. Give the ground state term for each. Gas phase ion: Ni 2+ Cr 2+ Cr 3+ Cu + Fe 3+ V 3+ Oct. Complex: Ni 2+ Cr 2+ Cr 3+ Cu + Fe 3+ V 3+ Tet complex: Ni 2+ Cr 2+ Cr 3+ Cu + Fe 3+ V How many microstates make up 4f 3 4 F 2s 1 2p 4 5 D e g 2 t 2g 1 How many microstates make up the lowest energy configuration for a gas phase Cr atom. (You should look up the correct configuration)? What is the ground state term? 3.a) The terms arising from d 6 are 5 D, 3 H, 3 G, 3 F, 3 F, 3 D, 3 P, 3 P, 1 I, 1 G, 1 G, 1 F, 1 D, 1 D, 1 S, 1 S Show that these correctly add up to the total number of microstates = 10!/(4! X 6!). b) The number of microstates with M L = M s =0 will exactly equal the total number of terms arising. Why? See how many of the 16 microstates with M L = M s = 0 for the d 6 case you can come up with. 4.a) Using the electrostatic CFSE calculations tabulated in the handouts, give the CFSE for Ni 2+ in a weak field (2 unpaired electrons) and strong field (diamagnetic where possible) for the following. Weak field : Linear, trigonal, tetrahedral, square pyramidal, trig bipy, octahedral or square planar? strong field : Linear, trigonal, tetrahedral, square pyramidal, trig bipy, octahedral or square planar. 5. Obtain 10Dq from spectra of the M(H 2 O) 6 +n ions in the handout (where easily done) and compare with tabulated values.

3 CHEM 3030 Space Group Exercises ST3A Refer to posted space group tables for C2/c, P2 1 /c, P , Pbcn Pnnm, Pm3m and Fm3m. ( Convention is x down, y across and Z out of page.) 1. C2/c Identify the 8 general positions by labeling the O s in the diagram. Use 1-4 in order listed and 1c-4c for centred objects. 1 =xyz etc. 2. P2 1 /c assign each general position with the symmetry element that generates it from xyz. inversion at origin screw along b at z =1/4 C glide perp to b at b = ¼ P screw parallel to a b and c 3. Note the similar coordinates for Pm3m and Fm3m in space group tables. Deduce the space group for Im3m. Fe crystallizes in Im3m with Z =2. Give location of all atoms. Systematic Absences 1. The reflection 030 has zero intensity. Which of the 7 space groups are possible. 2.EXERCISE : Consult the space group tables for P , Pbcn, and Pnnm. Identify which crystal is consistent with each space group Crystal present 050 absent Crystal present absent Crystal present absent SITE SYMMETRY. 1. In which of the 7 space groups above could the following crystallize with Z =2? with Z =4? The Hermann-Maguin and Schonflies symbols are given to assist you. A. octahedral CrF 6 Oh = m3m B. tetrahedral TiI 4 Td = -43m C. square PtI 4 D 4h = 4/mmm C 2h = 2/m C 2 v = mm2 2. Which of the 7 space groups can accommodate the following with Z =4. A. optically pure d- o(acac) 3 B. racemic Co(acac) 3 3. A. If butane crystallized in Pbcn with Z =4 which rotamers would be expected and where would they lie? B. How or could trans PtL 2 X 2 crystallize in PbCn with Z =4? C. cis PtL 2 X 2 Crystallography Problem Set

4 CaF 2 crystallizes in the cubic space group Fm3m with Z =4, a= A. 1. Obtain the density. 2. Use the space group tables to identify the location of all atoms in the unit cell. 3. Compute the Ca-F bond length and the shortest Ca-Ca distance. 4. Compute the following structure factors F(000), F(100), F(200), F(111), F(123) assuming scattering factors f ca = 20 and f F = Using the structure factor expression prove that a 2 1 along the b axis results in systematic absences (0,k,0) for k odd. 6. Give the coordinates of the points generated by the sequence of operations X,Y,Z (2 1 along b) (Mirror in xz plane) c glide in xz plane X,Y,Z ( 2 along b) inversion at origin mirror in xy plane 7.a) Provide diagrams for the rectangular 2 dimensional space group Cmm. Mirrors are located along both the x and y axes and half way between. As in the handouts one figure shows object locations and the other symmetry elements. Identify the locations of a C2 axis and glide planes also generated. Provide the coordinates of the 8 general positions. B) Diagram a stickman in flatland space group Cmm with Z =4 C) Which of cis or trans dibromoethylene or tetrabromoethylene could crystallize in the 2D space group Cmm with Z = 2? Sketch the unit cell. 8. Show how [Cu(NH 3 ) 4 ][NO 3 ] 2 5H 2 O could crystallize in the two dimensional space group Pmm with Z =1. Use a small square to denote the Cu cation, a triangle for the nitrate ion and a O for the waters. Ignore H s. All moieties lying within or on the edge of the cell must be shown.

5 ST3C. Crystallography Problem Set ANSWERS CaF 2 crystallizes in the cubic space group Fm3m with Z =4, a= A. 1. Obtain the density. density = MW X 4 / (0.603 X a 3 ) = 3.19 gm/cm 3 2. Use the space group tables to identify the location of all atoms in the unit cell. Ca at Wcoff site a, F at Wcf c. 3. Compute the Ca-F bond length and the shortest Ca-Ca distance. Ca-F = sqr(3 x (0.25 x 5.34) 2 ) or 3 1/2 x 5.34/4 = 2.31 Å Ca-Ca = 2 1/2 x 5.34/2 = 3.78 Å 4. Compute the following structure factors F(000), F(100), F(200), F(111), F(123) assuming scattering factors f ca = 20 and f F = 9. SUM over all 4 Ca locations and all 8 F locations. F(000) = 4 x (20+2X9) = 152 electrons F(200) = 4{20) 8(9) = 2 F(100)=F(123) =0 F(111) = Using the structure factor expression prove that a 2 1 along the b axis results in systematic absences (0,k,0) for k odd. see notes 6. Give the coordinates of the points generated by the sequence of operations X,Y,Z (2 1 along b) -x,y+1/2, -z y-1/2,1/2-z (Mirror in xz plane) x, ½-y,-z * c glide in xz plane -x, X,Y,Z ( 2 along b) -x,y, -z inversion at origin x,-y,z mirror in xy plane x,-y,-z * here we use the mirror at y =1/2. if mirror at y=0 then -1/2-y. 7.a) Provide diagrams for the rectangular 2 dimensional space group Cmm. Mirrors are located along both the x and y axes and half way between. As in the handouts one figure shows object locations and the other symmetry elements. Identify the locations of a C2 axis and glide planes also generated. Provide the coordinates of the 8 general positions. (x,y) (-x,y) (x,-y_ (-x,-y) and (½,1/2)+ each of these. B) Diagram a stickman in flatland space group Cmm with Z =4 on either mirror but not both gives 4 locations C) Which of cis or trans dibromoethylene or tetrabromoethylene could crystallize in the 2D space group Cmm with Z = 2? Sketch the unit cell. (for 2D we assume molecule cannot project into third dimension) For Z =2 needs to have 2 mirrors (other than plane of molecule) only tetrabromo. For Z =4 cis or tetra but not trans. 8. Show how [Cu(NH 3 ) 4 ][NO 3 ] 2 5H 2 O could crystallize in the two dimensional space group Pmm with Z =1. Use a small square to denote the Cu cation, a triangle for the nitrate ion and a O for the waters. Ignore H s. All moieties lying within or on the edge of the cell must be shown. Cu on mm site at site origin or ½ ½ NH 3 general at (xn,yn) or two on mirrors at (0,yn) (xn,0) nitrate on mirrors waters in general plus one on other mm site 4+ 1 =5.

6 CHEM 3030 Exploring Ni(stilbenediamine) 2 (Cl 2 CHCOO) 2 crystal structures. Two RES files Ni blue and Ni yellow have been generated from the atom list in the original manuscript by Nyburg. Examine each using the HG software. The space group table for P2 1 /c is posted on the 3030 website. You should be able to generate the one for P-1 yourself. BLUE crystallizes in P2 1 /c. Z =2. 1. Identify the crystal system. Is the Nickel in a general or special position? What symmetry is imposed if any? 2. What is the geometry about the Nickel? 3. How many dichloroacetates are in the asymmetric unit? Is any symmetry imposed on them? Why? 4. How many water oxygens are in the unit cell? 5. How many waters are present in the asymmetric unit? Are they in general or special positions? 6. What are the two most intense reflections in the Xray powder pattern and approximately what angle are they found at? Compute theta for Cu radiation assuming an orthorhombic cell ( angles 90). 7. Assuming Ni scattering dominates show why these two reflections are the most intense (see Eq 2). YELLOW crystallizes in P-1 with Z =3. 1. How do the three nickels differ in geometry in this crystal? Which are in general and which in special positions? 2. What symmetry is imposed in each case. 3. Assuming Ni scattering dominates explain the relative intensity of the 100, 010, and 001 reflections in the x-ray powder pattern. 4. Are the two Ni acetate bonds required to be the same length? Explain 5. Explain the molecular formula in the two cases. blue-nil 2 X 2 4H 2 O and yellow NiL 2 X 2 4/3 water 2/3 ethanol on the basis of the asymmetric unit and number of equivalent positions in each case. 6. Compare the Ni-N bond lengths in the square and octahedral forms. Explain the differences using VBT, CFT, and MOT. 7. Predict the expected magnetism and visible spectra of the two crystals.