Preview Inorganic Chemistry Molecular Facets (De Gruyter Textbook) by Ram Charitra Maurya (2021)

Preview Inorganic Chemistry Molecular Facets (De Gruyter Textbook) by Ram Charitra Maurya (2021) Preview Inorganic Chemistry Molecular Facets (De Gruyter Textbook) by Ram Charitra Maurya (2021) Preview Inorganic Chemistry Molecular Facets (De Gruyter Textbook) by Ram Charitra Maurya (2021) Preview Inorganic Chemistry Molecular Facets (De Gruyter Textbook) by Ram Charitra Maurya (2021) Preview Inorganic Chemistry Molecular Facets (De Gruyter Textbook) by Ram Charitra Maurya (2021)

Ram Charitra MauryaInorganic Chemistry

Molecular Symmetry and Group Theory.

Approaches in Spectroscopy and Chemical Reactions

Ram Charitra Maurya Inorganic

ChemistrySome New Facets

Prof Dr Ram Charitra Maurya

Ph.D., D.Sc, CChem FIC (India), CChem FRSC (UK)

Professor of Inorganic Chemistry

Former Head, Department of Chemistry and Pharmacy, and

Dean, Faculty of Science

Rani Durgavati University

Library of Congress Control Number: 2020952731

Bibliographic information published by the Deutsche Nationalbibliothek

The Deutsche Nationalbibliothek lists this publication in the Deutsche Nationalbibliografie; detailed bibliographic data are available on the Internet at http://dnb.dnb.de.

© 2021 Walter de Gruyter GmbH, Berlin/Boston

Cover image: Piranka/Gettyimages

Typesetting: Integra Software Services Pvt Ltd.

Printing and binding: CPI books GmbH, Leck

www.degruyter.com

Dedicated to

My wifeMrs Usha Rani Maurya,who has always been a source of inspiration for me

throughout my growth

&

My sons, Ashutosh and Animesh; daughter, Abhilasha; and son-in-law, Adarsh

forencouragement

During my long journey of teaching span of more than 40 years in three differentuniversities at B.Tech., M.Sc., M.Phil and Ph.D levels, I had always realized thelack of textbooks in Inorganic Chemistry that covers most of the topics for in-depth teaching of the subject matters Moreover, I was also in quest of readingmaterials in the form of research papers, reviews and books, so that curriculum atPostgraduate, M.Phil and Ph.D coursework levels in any university of India andabroad too can be revised for updating manpowers in Chemistry for manifold ap-plications The present book, entitled Inorganic Chemistry: Some New Facets, in-corporating 10 chapters, is designed to meet out the objectives mentioned above.Although many more topics are still not covered in this book only because of look-ing over the too much bulk of the book, they will be given attention in its nextvolume

The book also aims to assist students in preparing for competitive tions, viz NET, GATE, SLET and Doctoral Entrance Test (DET) particularly in India.Each chapter ends with different multiple choice, short answer and long answerquestions, covering the topics discussed in the chapter to allow an opportunity tothe students for their self-evaluation

examina-In completing a book of this nature, one accumulates gratefulness to the ous authors and editors of books, research papers, reviews and monographs on therelevant topics I have consulted these sources freely and borrowed their ideas andviews with no hesitation in preparing the present manuscript These sources are ac-knowledged and listed in bibliography, and I am highly thankful to these authors.Moreover, the present book is the outcome of my teaching of the subject for morethan 40 years to several batches of Masters, M.Phil and Ph.D coursework students

previ-at the Department of Chemistry, Atarra P.G College, Atarra (Bundelkhand University,Jhansi, U.P., India) and Rani Durgavati University, Jabalpur (M.P.), India I havebenefited enormously from the response, questions and criticisms of my students.Looking over the problems of students in learning the subject, I have tried mybest to present the subject with a student-friendly approach, that is, expressing it in

an interactive manner and in simple language with many illustrative examples.Moreover, the mathematical parts wherever required are given in details to makethe subject easily understandable Therefore, I hope that the book will serve as atext for M.Sc., M.Phil and Ph.D coursework students of Chemistry

My endeavour will be amply rewarded if the book is found helpful to the dents and teachers Despite serious attempts to keep the text free of errors, it would

stu-be presumptuous to hope that no error has crept in I shall stu-be grateful to all thosewho may care to send their criticism and suggestions for the improvement of thebook on my e-mail ID (rcmaurya1@gmail.com)

The writing of this book was initiated in September 2018 at 4515 WavertreeDrive, Missouri City, Texas 77459, USA, during our stay with my daughter, Dr.Abhilasha, and son-in-law, Dr Adarsh, for which they deserve thanks.

Last but not the least, I am thankful to my wife, Mrs Usha Rani Maurya, for herpatient understanding of the ordeal which she had to undergo due to my almostone-sided attention during the completion of this challenging task I am also in-debted to my students for their encouragement and cooperation

B-95, Priyadarshini Colony, Dumna Airport Road, (Author)Jabalpur (M.P.), India

1.2 Postulates of VSEPR theory: Sidgwick and Powell 1

1.3 Rules proposed by Gillespie and Nyholm 1

1.3.1 Rule 1 Spatial arrangement of electron pairs around the central

atom of a given molecule/ion 1

1.3.2 Rule 2 Regular and irregular geometry: presence of hybrid

orbitals containing bond pairs and lone pairs 3

1.3.3 Rule 3 Effect of electronegativity: repulsions exerted by bond

pairs decrease as the electronegativity of the bonded atomincreases 6

1.3.4 Rule 4 Multiple bonds exert a stronger repulsion 6

1.3.5 Rule 5 Repulsions between electron pairs in filled shells are

larger than those between electron pairs in incomplete

shells 6

1.4 Exceptions to the VSEPR model, ligand–ligand repulsion and the

ligand close packing model 8

1.5 Applications of VSEPR theory 10

1.6 Shortcomings of VSEPR theory 20

2.1 Localized and delocalized bonds 27

2.1.1 Localizedσ- and π-bonds 27

2.1.2 Delocalizedπ-bond(s) 27

2.2 Basic principles of molecular orbital theory: polyatomic

molecules or ions involving delocalizedπ-bonding 272.2.1 Various steps involved in working out delocalizedπ-MOs 282.3 Delocalizedπ-bonding in non-cyclic polyatomic molecules

or ions 29

2.3.1 Ozone molecule (O3) 29

2.3.2 Nitrogen dioxide (NO ) molecule 32

2.3.3 Nitrite ion (NO2−) 35

2.3.4 Delocalizedπ-bonding in hydrazoic acid 38

2.3.5 Delocalizedπ-bonding in hydrazoic ion (N3 −) 41

2.3.6 Delocalizedπ-bonding in nitrate ion (NO3 −) 44

2.3.7 Delocalizedπ-bonding in BF3 48

2.3.8 Delocalizedπ-bonding in Cu2O molecule 50

2.4 Delocalizedπ-bonding in cyclic molecules 53

3.7.1 Bonding in boranes and higher boranes/boron clusters:

molecular orbital approach 79

3.7.2 Molecular orbital approach 79

3.7.3 Formation of B–H–B bond 80

3.7.4 Formation of B–B–B bond 83

3.8 Topology of boranes (Lipscomb’s rule): s t y x four-digit coding of

bonding in boranes 87

3.8.1 Utility of Lipscomb’s rule 88

3.8.2 Validity of Lipscomb’s rule 88

3.8.3 Calculation of total number of VEs and number of bonds in

boranes without making use of Lipscomb’s rule 93

3.8.4 Limitations of Lipscomb’s topological scheme: Wade’s rules

relating the structures of boranes with their composition 95

3.10 Metallocarboranes or carborane complexes 105

3.10.1 Synthetic routes to metallocarboranes 106

3.10.2 Reactivity of metallocarboranes 112

Exercises 113

Chapter IV

Synthesis and reactivity of metal clusters, and their bonding based on

molecular orbital approach 117

4.2 Metal cluster and catalysis 117

4.3 Factors favouring for metal–metal bonding 119

4.3.1 Large energies of atomization 119

4.3.2 Low oxidation states 120

4.3.3 Presence of only limited number of electrons in the valence

shell 120

4.3.4 Suitable valence shell configurations 120

4.4 Evidence/identifying parameters for metal–metal bonding 1204.4.1 Molecular structure 120

4.4.2 Magnetic susceptibility 122

4.5 Classification of metal clusters 122

4.6 Synthesis of metal clusters 122

4.8 Bonding in metal clusters: molecular orbital approach 126

4.8.1 Two metal atoms with localized single or multiple bonds 1264.8.2 More than two metal atoms of same or different atomic numbers

with considerable delocalization of covalent bonding 130

Exercises 132

Chapter V

Stability constants of metal complexes: some aspects 137

5.2 Types of stability of metal complexes 138

5.2.1 Thermodynamic stability: stable and unstable complexes 1385.2.2 Kinetic stability: labile and inert complexes 138

5.3 Thermodynamic stability versus kinetic stability 139

5.4 Dissociation of a complex in solution: dissociation constant

(Kdiss) or instability constant (Ki) 140

5.5 Stepwise formation/stability constants and overall formation/

stability constants 141

5.5.1 Stepwise formation/stability constants 141

5.5.2 Overall formation/stability constants 142

5.5.3 Relationship between overall (βn) and stepwise stability

6.5.1 Metal–metal interaction 180

6.5.2 Spin exchange interaction through bridging of O2−or F−ions 1816.5.3 Effect of temperature on magnetic susceptibility

of anti-ferromagnetic substances 182

6.6 Magnetic moment from magnetic susceptibility 184

6.7 Curie and Curie–Weiss law: effect of temperature on χMcorrof

6.9.1 Calculations ofχdiaof some compounds 191

6.9.2 Utility of Pascal’s constants 195

6.10 Origin of magnetism: orbital and spin motion 195

6.10.1 Orbital magnetic moments (μl) 196

6.10.2 Spin magnetic moment (μs) 197

6.11 Quenching of orbital angular momentum: orbital contribution to

magnetic moment of Oh, Tdand square planar complexes 1986.11.1 What is quenching of orbital angular momentum? 198

6.11.2 Quenching of orbital angular momentum: explanation 198

6.11.3 Octahedral and tetrahedral complexes 198

6.11.4 Orbital contribution in square planar complexes 207

6.12 Magnetic properties of paramagnetic substances 207

6.12.1 Thermal energy and magnetic property 207

6.12.2 Multiplet widths large as compared to kT 208

6.12.3 Multiplet widths small as compared to kT 212

6.12.4 Multiplet widths comparable to kT 214

6.13 Anomalous magnetic moments 216

6.13.1 Octahedral complexes 216

6.13.2 Tetrahedral complexes 218

6.13.3 Square planar complexes 218

6.13.4 Factors responsible for anomalous magnetic moments 218

6.14 Experimental methods of determination of magnetic

susceptibility 229

6.14.1 Gouy method 229

6.14.2 Faraday’s method 233

6.14.4 Advantages and disadvantages of different techniques 235

6.15 Uses of magnetic moments data of complexes 236

6.16 Limitations of valance bond theory: magnetic behaviour of

complexes 244

Contents XIII

6.17 Crystal field theory and magnetic behaviour of complexes 2466.17.1 Octahedral complexes 247

7.5 Lability and inertness in octahedral complexes: kinetically labile

and kinetically inert complexes 265

7.5.1 Kinetically labile complexes 266

7.5.2 Kinetically inert complexes 266

7.6 Lability/internees versus thermodynamically stable/unstable

complexes 266

7.7 Interpretation of lability and inertness of transition metal

complexes 267

7.7.1 The valence bond theory approach 267

7.7.2 Crystal field theory 269

7.8 Substitution reactions in octahedral complexes: acid and base

hydrolysis 273

7.9 Mechanism of acid hydrolysis (aquation) of different types of Oh

complexes 273

7.9.1 Mechanism of acid hydrolysis when no inert ligand in the

complex is aπ-donor or π-acceptor 274

7.9.2 Mechanism of acid hydrolysis in octahedral complexes in which

the inert ligand is aπ-donor 279

7.9.3 Mechanism of acid hydrolysis in octahedral complexes in which

the inert ligand is aπ-acceptor 283

7.10 Base hydrolysis 286

7.11 Mechanism of base hydrolysis 287

7.11.1 Associative SN2mechanism for base hydrolysis 287

7.11.2 SN1(CB) mechanism for base hydrolysis 288

7.12 Observed reaction rates in different cases: explanation through

SN1(CB) mechanism 289

7.12.1 Second-order kinetics of base hydrolysis 289

7.12.2 Base hydrolysis of [Co(NH3)5Cl]2+at high concentration of OH− 2907.12.3 Base hydrolysis of ammine complexes by nucleophiles/bases

NO2−, NCS−and N3− 290

7.12.4 Base hydrolysis of [M(en)2Cl2]+[M=Co(III) or Rh(III)] 290

7.12.5 Hydrolysis of octahedral complex ions having no acidic

hydrogen 291

7.12.6 Catalytic role of OH−ions in hydrolysis of octahedral [Co(en)2

(NO2)Cl]+ion in non-aqueous medium 292

7.12.7 Base hydrolysis of Co(III) ammine complexes in presence of

H2O2 293

7.13 Stereochemistry of intermediates formed during base hydrolysis

of Co(III) ammine complexes 294

7.14 Reaction involving replacement of coordination water: anation

7.16.3 Stereochemistry of SN2mechanism in substitution reaction of

square planar complexes 304

7.17 Role of some ligands preferentially direct the substitution of a

ligand trans to themselves in square planar complexes: trans

7.19 Mechanism of the trans effect 313

7.20 Theory of trans effect 314

7.21 The polarization theory 314

7.22 Theπ-bonding theory 315

7.23 Trans effect in octahedral complexes 317

7.23.1 Introduction 317

7.23.2 STEs in octahedral metal complexes 318

7.23.3 KTEs in octahedral metal complexes 323

7.24 Redox reactions: electron transfer reactions 325

7.24.1 Introduction 325

7.24.2 Categories of redox reactions 325

7.25 Mechanism of electron transfer reaction in solution 328

7.25.1 Outer sphere mechanism 329

7.25.2 Inner sphere (or ligand bridged) mechanism 336

7.26 Two-electrons transfer reactions 340

Exercises 342

Chapter VIII

Bonding in transition metal complexes: molecular orbital theory approach 349

8.2 Evidence of covalent bonding in complexes 350

8.2.1 Electron spin resonance spectra 350

8.2.2 Nuclear magnetic resonance spectra 351

8.2.3 Nuclear quadrupole resonance studies 352

8.2.4 Intensities of d–d transitions 352

8.2.5 Interelectronic repulsion: the nephelauxetic effect 352

8.3 Molecular orbital theory: transition metal complexes 355

8.3.1 Introduction 355

8.3.2 Qualitative aspect of MOT 355

8.4 Sigma (σ) bonding in octahedral complexes 356

8.4.1 Energy order of orbitals and their filling with electrons 3618.5 Pi (π)-bonding in octahedral complexes 365

8.5.1 Types ofπ-bonds 367

8.5.2 Formation of LGOs forπ-bond formation 368

8.5.3 Effect ofπ-bonding on the magnitude of Δo: construction of MO

energy level diagram/types ofπ-bonding complexes 370

8.6 Tetrahedral complexes 379

8.6.1 Sigma (σ) bonding in tetrahedral complexes 380

8.6.2 π-Bonding in tetrahedral complexes 386

8.7 Square planar complexes 393

8.7.1 σ-Bonding in square planar complexes 393

8.7.2 π-bonding in square planar complexes 395

9.2.1 Valance bond approach 411

9.2.2 Molecular orbital approach 412

9.3 Bonding in bis(arene) complexes with special reference

to bis(π-benzene)-chromium 433

9.3.1 Introduction 433

9.4 Bonding in bis(π-benzene)chromium 434

9.4.1 Valance Bond (VB) approach 434

9.4.2 Molecular orbital (MO) approach 435

9.4.3 Eclipsed form of bis(π-C6H6)2Cr 441

10.2 Inorganic qualitative analysis 451

10.2.1 Design of ignition tube apparatus 452

10.2.2 Test of radicals using ignition tube apparatus technique 45210.2.3 Test of radicals with reagent filter paper 455

10.2.4 Test of acid radicals using reagent solution 457

10.2.5 Test of basic radicals using reagent solution 461

10.3 Synthesis of inorganic compounds and metal complexes 46910.3.1 Synthesis of mercuric thiocyanate, Hg(SCN)2from mercuric

chloride 470

10.3.2 Synthesis of zinc thiocyanate Zn(SCN)2from zinc chloride 47110.3.3 Synthesis of cadmium thiocyanate Cd(SCN)2from cadmium

chloride 472

10.3.4 Synthesis of copper(I) sulphate, Cu2SO4 473

10.3.5 Synthesis of potassium chlorochromate (VI), K[CrO3Cl] 474

10.3.6 Synthesis of mercury(II) tetrathiocyanatocobaltate(II) complex,

HgII[Co(SCN)4] 476

10.3.7 Synthesis of diaquabis(methyl acetoacetato)nickel(II) complex 47710.3.8 Synthesis of diaquabis(ethyl acetoacetato)cobalt(II) complex 48010.3.9 Synthesis of bis(methyl acetoacetato)copper(II) monohydrate

complex 481

10.3.10 Synthesis of dichlorobis(dimethyl sulphoxide)copper(II),

[CuCl2(DMSO)2] (DMSO = dimethyl sulphoxide) 483

10.3.11 Synthesis of dimeric tris(thiourea)copper(I) sulphate 485

10.3.14 Synthesis of sodium nitrosylpentacyanoferrate(II) dihydrate/

sodium nitroprusside, Na2[Fe(NO)(CN)5]⋅2H2O 493

10.3.31 Synthesis of ammonium tetrathiocyanatodiamminechromate(III)

mono-hydrate, NH4[Cr(SCN)4(NH3)2]⋅H2O (Reinecke salt) 52510.3.32 Synthesis of potassium dichromate, K2Cr2O7 527

10.3.33 Synthesis of potassium manganate (VI), K2MnO4 528

10.3.34 Synthesis of potassium dioxalatodiaquachromate(III) dihydrate,

10.3.38 Synthesis of tetraaqua-bis(o-sulphobenzimide)nickel(II) 53810.3.39 Synthesis of tetraaqua-bis(o-sulphobenzimide)iron(II) 538

rhodium(III), mer-[RhIIICl3(CO)(PPh3)2] 548

10.4 Synthesis of metal oxide nanoparticles 550

10.4.1 Synthesis of copper oxide (CuO) nanoparticles 551

10.4.2 Synthesis of manganese dioxide nanoparticles 552

10.4.3 Synthesis of chromium oxide (Cr2O3) nanoparticles 554

10.4.4 Synthesis of Co3O4nanoparticles 555

10.4.5 Synthesis of ZnO nanoparticles 555

10.4.6 Synthesis of NiO nanoparticles 556

10.4.7 Synthesis of MgO nanoparticles 556

Exercises 557

Appendix I Some aspects of modern periodic table 563

Appendix II Units, fundamental physical constants and conversions 577

Appendix III Nomenclature of inorganic compounds: the rules 583

Appendix IV Symmetry operations and point groups in molecules 605

Appendix V Prediction of infrared and Raman active modes in molecules

belonging to icosahedral (Ih) point group 625

Bibliography 637

Index 641

repul-According to this theory, the shape of a given species (molecule or ion) depends onthe number and nature of electron pairs surrounding the central atom of the species.

1.2 Postulates of VSEPR theory: Sidgwick and Powell

The various postulates of this theory are as follows:

(i) The unpaired electrons in the valence shell of central atom form bond pairs(bps) with surrounding atoms while paired electrons remain as lone pairs (lps).(ii) The electron pairs surrounding the central atom repel each other Consequently,they stay as far apart as possible in space to attain stability

(iii) The geometry and shape of the molecule depend upon the number of electronpairs (bond pair as well as lone pair) around the central atom

(iv) The geometrical arrangements of electron pairs with different number of tron pairs around central atom are given in Table 1.1

elec-1.3 Rules proposed by Gillespie and Nyholm

The following rules have been proposed byRonald Gillespie and Ronald SydneyNyholm of University College of London to explain the shape of a number ofpolyatomic molecules or ions

1.3.1 Rule 1 Spatial arrangement of electron pairs around the central atom

of a given molecule/ion

The electron already present in the valence shell of the central atom of the givenspecies plus the electron acquired by the central atom as a result of bonding with

Table 1.1: Shapes of the various molecules depending upon the number of shared electrons around the central metal atom.

120o Triangular planar

B

120o

90o

Trigonal bipyramidal

6

90o

90oB

B

A B

Octahedral SF6, TeF6

2 Chapter I Valence shell electron pair repulsion (VSEPR) theory