Intramolecular Spodium Bonds in Zn(II) Complexes: Insights from Theory and Experiment

Total Page:16

File Type:pdf, Size:1020Kb

Intramolecular Spodium Bonds in Zn(II) Complexes: Insights from Theory and Experiment International Journal of Molecular Sciences Article Intramolecular Spodium Bonds in Zn(II) Complexes: Insights from Theory and Experiment Mainak Karmakar 1, Antonio Frontera 2 , Shouvik Chattopadhyay 1,* , Tiddo J. Mooibroek 3,* and Antonio Bauzá 2,* 1 Department of Chemistry, Inorganic Section, Jadavpur University, Kolkata 700 032, India; [email protected] 2 Departament de Química, Universitat de les Illes Balears, Crta. de Valldemossa km 7.5, 07122 Palma (Baleares), Spain; [email protected] 3 van ‘t Hoff Institute for Molecular Sciences, Universiteit van Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands * Correspondence: [email protected] (S.C.); [email protected] (T.J.M.); [email protected] (A.B.) Received: 30 August 2020; Accepted: 22 September 2020; Published: 25 September 2020 Abstract: Two new dinuclear zinc(II) complexes, [Zn (µ -OAc)(L1) ]I MeOH (1) and [Zn (µ - 2 1,3 2 · 2 1,3 OAc)(L2)(NCS)] (2), (where HL1 = 2-(((3-(dimethylamino)propyl)amino)methyl)-6-methoxy-phenol 2 and H2L = 2,20-[(1-Methyl-1,2-ethanediyl)bis(iminomethylene)]bis[6-ethoxyphenol]) have been synthesized and characterized by elemental and spectral analysis. Their X-ray solid state structures have been determined, revealing the existence of intramolecular Zn O spodium bonds in both ··· complexes due to the presence of methoxy (1) or ethoxy (2) substituents adjacent to the coordinated phenolic O-atom. These noncovalent interactions have been studied using density functional theory (DFT) calculations, the quantum theory of “atoms-in-molecules” and the noncovalent interaction plot. Moreover, a search in the Cambridge structure database (CSD) has been conducted in order to investigate the prevalence of intramolecular spodium bonds in Zn complexes. To our knowledge this is the first investigation dealing with intramolecular spodium bonds. Keywords: zinc complexes; spodium bonds; σ-hole interactions; CSD analysis; DFT calculations 1. Introduction Noncovalent interactions are very important in many fields of research, including molecular recognition, crystal engineering and catalysis [1–3]. Among the great deal of noncovalent forces, investigations on σ-hole interactions [4,5] are growing very fast and are definitively recognized by the scientific community as an alternative to the ubiquitous hydrogen bonding [6]. Very recently, the attractive interaction between elements of Group 12 of the Periodic Table and any electron rich ‘accepting’ atom (:A) [7,8] has been termed as a spodium bond (SpB) [9]. Therefore, the SpB has become a new member of the σ-hole family of interactions and it is adequate to differentiate the coordination bond (high covalent character) typical of transition metals from the noncovalent contact. SpBs are directional, the electron rich atom is located at distances that are longer than the sum of covalent radii and they are considerably weaker than coordination bonds. Moreover, the participation of the antibonding σ*(Sp–Y, where Y can be any atom) in the SpB bonding interaction (Y–Sp :A) has been ··· evidenced [9], as is common in σ-hole interactions [4,5]. This manuscript reports the synthesis and X-ray characterization of two new Zn(II) complexes that exhibit intramolecular SpBs. The utilization of two different tridentate and tetradendate ligands allows analyzing the interaction in two different Zn-coordination modes, square-pyramidal in (1) Int. J. Mol. Sci. 2020, 21, 7091; doi:10.3390/ijms21197091 www.mdpi.com/journal/ijms Int. J. Mol. Sci. 2020, 21, 7091 2 of 14 Int. J. Mol. Sci. 2020, 21, 7091 2 of 14 andpseudotetrahedral pseudotetrahedral in (2). in The (2). SpBs The in SpBs both incompounds both compounds have been have studied been using studied density using functional density functionaltheory (DFT) theory calculations (DFT) calculations and characterized and characterized by a combination by a combination of the quantum of the quantumtheory of theoryatoms ofin atomsmolecules in molecules (QTAIM) (QTAIM) [10] and [10 the] and noncovalent the noncovalent interaction interaction (NCI) (NCI) method method [11]. [11Moreover,]. Moreover, the theCambridge Cambridge Structural Structural Database Database (CSD) (CSD) [12] [12 has] has been been examined examined in in order order to to investigate investigate the prevalence ofof intramolecularintramolecular SpBsSpBs inin Zn(II)Zn(II) complexescomplexes andand theirtheir geometric geometric features. features. 2.2. Results and Discussion 2.1.2.1. Synthesis InIn this this work, work, two two acetate acetate bridged bridged dinuclear dinuclear zinc complexes zinc complexes have been have synthesized been synthesized using reduced using 1 2 1 reducedSchiff bases Schi ff HLbases1 and HL Hand2L2 Has2 L ligands.as ligands. HL1 HLwas wasprepared prepared by by1:1 1:1 condensation condensation of of 3-3‐ methoxysalicylaldehydemethoxysalicylaldehyde and andN, NN-dimethyl-1,3-diaminopropane,N‐dimethyl‐1,3‐diaminopropane in methanol in methanol and subsequent and subsequent reduction 2 usingreduction NaBH using4 following NaBH4 following a literature a literature method [ 13method–15]. In[13–15]. the same In the way, same H2 way,L was H2L prepared2 was prepared by 2:1 condensationby 2:1 condensation of 3-ethoxysalicylaldehyde of 3‐ethoxysalicylaldehyde and rac and-1,2-diaminopropane rac‐1,2‐diaminopropane in methanol in methanol followed followed by the 1 reductionby the reduction with NaBH with4. NaBH Methanol4. Methanol solution solution of HL on of reaction HL1 on with reaction zinc acetatewith zinc dihydrate acetate anddihydrate potassium and 2 iodidepotassium in a iodide 2:2:1 molar in a 2:2:1 ratio molar produced ratio complexproduced1 .complex On the other1. On hand,the other methanol hand, methanol solution of solution H2L on of reactionH2L2 on withreaction zinc with acetate zinc dihydrate acetate dihydrate and sodium and thiocyanate sodium thiocyanate in a 1:2:1 molar in a 1:2:1 ratio molar produced ratio complex produced2. Thecomplex synthetic 2. The routes synthetic to the routes complexes to the1 complexesand 2 are shown 1 and 2 in are Figure shown1. in Figure 1. FigureFigure 1.1. Synthetic routesroutes toto complexescomplexes 11 andand 22.. Int. J. Mol. Sci. 2020, 21, 7091 3 of 14 2.2. Description of Compounds 1 and 2 A perspective view of complexes 1 and 2 along with selective atom numbering scheme is depicted in Figure 2a,b respectively. 1 crystallizes in the orthorhombic space group P212121 and its asymmetric unit consists of an acetato bridged dinuclear zinc(II) L12 complex, one I– counter anion and a methanol solvent molecule. Each zinc is coordinated to the tridentate L1 via two amine N‐ atoms, one bridging acetate ligand and two bridging phenolate oxygen atoms (see Supplementary Figure S1). Both penta‐coordinated zinc(II) centers are in a distorted square pyramidal geometry (see SupplementaryInt. J. Mol. Sci. 2020 ,Figures21, 7091 S2 and S3). The asymmetric unit contains one lattice methanol molecule3 that of 14 is H‐bonded to the I− counter anion. The counter ion is also H‐bonded to N4–H4 of the reduced Schiff base ligand. 2.2. Description of Compounds 1 and 2 Compound 2 (Figure 2b and Supplementary Figure S4) crystallizes in the triclinic space group Pī andA perspectivedoes not contain view of additional complexes 1ionsand or2 alongsolvent with molecules selective atomin its numbering asymmetric scheme unit. isZn2 depicted is N‐ coordinatedin Figure2a,b to respectively. the thiocyanate,1 crystallizes connected in theto O6 orthorhombic of the bridging space acetate group andP21 2bound121 and to its two asymmetric bridging 1 – phenolateunit consists O‐ ofatoms an acetato to form bridged a distorted dinuclear tetrahedron zinc(II) (see L 2 complex, Supplementary one I counter Figure S5). anion Zn1 and is asituated methanol in asolvent distorted molecule. square Each pyramidal zinc is environment coordinated to where the tridentate the ligand L1 [O1,N1,N2,O3]via two amine N-atoms,donor atoms one form bridging the baseacetate of ligandthe pyramid and two and bridging O5 of the phenolate bridging oxygen acetate atomsis at the (see apex. Supplementary The coordination Figure distances S1). Both of penta-coordinatedcompounds 1 and 2 zinc(II) are given centers in Table are in1 and a distorted range from square 1.92 pyramidal to 2.21 Å. geometryThese distances (see Supplementary are similar or slightlyFigures S2longer and S3).that The the asymmetric sum of covalent unit contains radii ( oneΣRcov lattice = 1.93 methanol and 1.86 molecule Å for thatZn+N is H-bonded and Zn+O, to respectively)the I− counter and anion. can Thebe considered counter ion as is normal also H-bonded [16]. to N4–H4 of the reduced Schiff base ligand. Figure 2. Perspective ball ball and stick view of the complexes 1 (a) and 2 (b) along with selective atom numbering scheme (only the coordinating atoms are labeled forfor clarity).clarity). TableCompound 1 also 2gathers(Figure longer2b and Zn Supplementary∙∙∙O distances Figure (values S4) in crystallizesitalics) where in thethe triclinic O‐atom space belongs group to the P ¯ı methoxyand does not(in L contain1) or ethoxy additional (in L2 ions) substituent or solvent of molecules the aromatic in its ring. asymmetric These distances unit. Zn2 are is N-coordinated around 0.8 Å longerto the thiocyanate,than ΣRcov and, connected consequently, to O6 can of the be bridgingconsidered acetate as intramolecular and bound tospodium two bridging bonds, phenolateas further analyzedO-atoms to below. form These a distorted interactions tetrahedron are depicted (see Supplementary in Figure 3 as Figure black S5).dashed Zn1 lines. is situated In compound in a distorted 1 the SpBssquare are pyramidal located opposite environment to the Zn–O(acetate) where the ligand coordination [O1,N1,N2,O3] bonds donorat an angle atoms of form~170°. the In basecompound of the pyramid2, the ethoxyde and O5 O of‐atoms the bridging are located acetate opposite is at the the phenoxy apex. The O’s coordination at an angle of distances ~145°.
Recommended publications
  • Structures of Cobalt, Zinc and Lead Niobates Based On
    1 Structures at the Atomic Level of Cobalt, Zinc and Lead Niobates Raji Heyrovska Institute of Biophysics, Academy of Sciences of the Czech Republic, 135 Kralovopolska, 612 65 Brno, Czech Republic. Email: [email protected] The author has found in recent years that bond lengths are exact sums of the radii of adjacent atoms and or ions, where the ions have Golden ratio based radii. This work was prompted by the exciting observation last year of the Golden ratio in the magnetic properties of cobalt niobate. It is shown here that in cobalt and zinc niobates, cobalt, zinc and oxygen ions have Golden ratio based ionic radii, whereas in lead niobate, all atoms have covalent radii. Also, the angles at the single bond oxygen anion and atom are close to 1080, as in a pentagon. 1-3 The experimental finding of the E8 symmetry in the magnetic properties of cobalt niobate, CoNb2O6 provoked the author's interest to look into the atomic Nature Precedings : hdl:10101/npre.2011.6059.1 Posted 24 Jun 2011 structures of niobates. It was found4-7 in recent years that the Golden sections of the covalent bond lengths d(AA) between two atoms of the same kind are sums of the radii of Pauling's ionic resonance forms8, which are the cations and anions of the atom (A), i.e., d(AA) = d(AA)/φ + d(AA)/φ2, where φ (= 51/2 + 1)/2 is the Golden ratio. In particular, the inter-ionic distances in all alkali halides (M+X-) were shown to be exact sums of the Golden ratio based ionic radii, d(M+) = d(MM)/φ2 and d(X-) = d(XX)/φ.
    [Show full text]
  • Periodicity Covalent Radius
    Higher Chemistry St. Ninian’s High School Higher Chemistry: Unit 1 – Chemical Changes and Structure Part A – Periodicity and Bonding Lesson 2 – Periodicity: Covalent Radius Learning Outcomes By the end of this lesson you should know: 1. What is meant by the term covalent radius 2. That there is a pattern in the periodic table in covalent radius as you go along a period and down a group. 3. How to explain this pattern across the periods terms of the positive force of the nucleus and its pull on electrons 4. How to explain this pattern in groups in terms of number of occupied electron shells. Success Criteria You will have been successful in this lesson if you: 1. Read and learn the notes given 2. Watch the links provided 3. Complete Exercise 1.2 and check your answers. There is also a further reading section to help you gain more depth of understanding for this section. MS Teams will be monitored throughout the week by a chemistry teacher. If you need help or clarification with either the task or the content of the lesson, just ask. Links to Prior Knowledge You may wish to revise the following to help you understand this lesson: - National 5 chemistry – atomic structure, protons, electrons and electron arrangement CCS: Part A Lesson 2 – Periodicity: Covalent Radius Page 1 Higher Chemistry St. Ninian’s High School For reference, the periodic table is given in the data booklet. Download or print a copy of the Higher Chemistry Data Booklet from MS Teams or from the SQA website - https://www.sqa.org.uk/sqa/files_ccc/ChemistryDataBooklet_NewH_AH-Sep2016.pdf Notes Structure of the Atom The structure of an atom consists of a dense nucleus, containing protons which carry a positive charge and neutrons which carry no charge.
    [Show full text]
  • Atomic Radius
    Atomic Radius What is Atomic radius? Atomic radius is generally stated as being the total distance from an atom’s nucleus to the outermost orbital of electron. In simpler terms, it can be defined as something similar to the radius of a circle, where the center of the circle is the nucleus and the outer edge of the circle is the outermost orbital of electron. As you begin to move across or down the periodic table, trends emerge that help explain how atomic radii changes The effective charge (Zeff) of an atom is the net positive charge felt by valance electron. Zeff greatly affect the atomic size of atom.As Zeff decreases the size of the atom increases Because there is more screening of the electron from the nucleus - Type of Atomic Radius - (based on types of bonds) 1.Covalent Radius 2.Ionic Radius 3.Metallic Radius 1 Covalent radius When a covalent bond is present between two atoms, the covalent radius can be determined. When two atoms of the same element are covalently bonded, the radius of each atom will be half the distance between the two nuclei because they equally attract the electrons. The distance between two nuclei will give the diameter of an atom, but you want the radius which is half the diameter. Ionic radius The ionic radius is the radius of an atom forming ionic bond or an ion. The radius of each atom in an ionic bond will be different than that in a covalent bond. This is an important concept. The reason for the variability in radius is due to the fact that the atoms in an ionic bond are of greatly different size.
    [Show full text]
  • Practice Periodic Table Review Name______
    Practice Periodic Table Review Name_________________ 1. An electron will emit energy in quanta when its 8. The elements in Group 2 are classified as energy state changes from 4p to A) metals B) metalloids A) 5s B) 5p C) 3s D) 6p C) nonmetals D) noble gases 2. Which electron configuration represents an atom 9. Which element has chemical properties that are in the excited state? most similar to the chemical properties of sodium? A) 1s22s22p63s2 B) 1s22s22p63s1 A) beryllium B) calcium C) 1s22s22p6 D) 1s22s22p53s2 C) lithium D) magnesium 3. In the electron-dot symbol, the dots represent 10. Which statement explains why sulfur is classified electrons located in as a Group 16 element? A) A sulfur atom has 6 valence electrons. B) A sulfur atom has 16 neutrons. A) s sublevels, only C) Sulfur is a yellow solid at STP. B) p sublevels, only D) Sulfur reacts with most metals. C) s and p sublevels, only D) s, p, and d sublevels 11. As the elements in Group 15 are considered in order of increasing atomic number, which 4. What is the highest principal quantum number sequence in properties occurs? assigned to an electron in an atom of zinc in the ground state? A) nonmetal ® metalloid ® metal A) 1 B) 2 C) 5 D) 4 B) metalloid ® metal ® nonmetal C) metal ® metalloid ® nonmetal 5. Which orbital notation represents a noble gas in D) metal ® nonmetal ® metalloid the ground state? 12. At STP, which element is a good conductor of A) B) electricity? A) chlorine B) iodine C) C) silver D) sulfur D) 13.
    [Show full text]
  • Python Module Index 79
    mendeleev Documentation Release 0.9.0 Lukasz Mentel Sep 04, 2021 CONTENTS 1 Getting started 3 1.1 Overview.................................................3 1.2 Contributing...............................................3 1.3 Citing...................................................3 1.4 Related projects.............................................4 1.5 Funding..................................................4 2 Installation 5 3 Tutorials 7 3.1 Quick start................................................7 3.2 Bulk data access............................................. 14 3.3 Electronic configuration......................................... 21 3.4 Ions.................................................... 23 3.5 Visualizing custom periodic tables.................................... 25 3.6 Advanced visulization tutorial...................................... 27 3.7 Jupyter notebooks............................................ 30 4 Data 31 4.1 Elements................................................. 31 4.2 Isotopes.................................................. 35 5 Electronegativities 37 5.1 Allen................................................... 37 5.2 Allred and Rochow............................................ 38 5.3 Cottrell and Sutton............................................ 38 5.4 Ghosh................................................... 38 5.5 Gordy................................................... 39 5.6 Li and Xue................................................ 39 5.7 Martynov and Batsanov........................................
    [Show full text]
  • A Review of (Pโƒ™D) ฯ•-Bonding in Silicon Compounds
    Union College Union | Digital Works Honors Theses Student Work 6-1968 A Review of (p→d) π-Bonding in Silicon Compounds Donald Robert Siebert Union College - Schenectady, NY Follow this and additional works at: https://digitalworks.union.edu/theses Part of the Chemistry Commons Recommended Citation Siebert, Donald Robert, "A Review of (p→d) π-Bonding in Silicon Compounds" (1968). Honors Theses. 2167. https://digitalworks.union.edu/theses/2167 This Open Access is brought to you for free and open access by the Student Work at Union | Digital Works. It has been accepted for inclusion in Honors Theses by an authorized administrator of Union | Digital Works. For more information, please contact [email protected]. A REVIE1!! OF (p~d) 7T-BO!mING IN SILICON CONPOU7mS by Donald Robert Siebert / i Senior Thesis Submitted in Partial Fulfillment of the Requirements of Graduation DEPARTMENT OF CHENLSTRY u:noN COLLEGE JU?:rE 1968 -i- ,'//IC)J.., ..::; e ·1 I tJ . I ~6f c,Z This Thesis Submitted by to the Department of Chemistry of Union College in partial fulfillment of the requirements of the degree of Bachelor of Science vii th a ·uajor in Chemistry is approved by [I -ii- CONTENTS I.Introduction------------------------------------ II.Silicon - Oxygen Bonding------------------------ 6 ·III.Silicon - Nitrogen Bond~ng ---------------------- 10 IV.Silicon - Halogen Bondin5 ----------------------- 13 V.Silicon - Carbon Bonding------------------------ 19 VI.Conclusions------------------------------------- 27 VII.Peferences -------------------------------------- 28 -iii- I. Introduction The elements of the second short ro~ of the perio- die table have five empty d-orbitals of sufficiently low energy to permit their use in bond formation. The five or- bitals are spatially arranged as the schematic diagram be- low shows: ~ )I( '( £.~~ x ')( Figure 1 ~l(~ g.)(4_ '(;i.
    [Show full text]
  • Short Notes on Periodic Table Modern Periodic Table: Earlier Scientists
    Short Notes on Periodic Table Modern Periodic Table: Earlier scientists assumed that the properties of elements are periodic functions of their atomic masses. On the basis of this assumption, Mendeleev placed 63 elements in a vertical column called groups and in horizontal rows called periods. This method was rejected as it could not explain the position of certain elements, rare earth metals, and isotopes. A scientist named Henry Moseley removed these defects and put forward the modern periodic table with the modern periodic law. Moseleys Periodic Law: He stated that the properties of elements are periodic functions of their atomic number. Modern Periodic Table: A tabular arrangement of elements in groups and periods which highlights the regular trends in properties of elements is defined as the periodic table. Features of Modern Periodic Table There are eighteen vertical columns known as groups in the modern periodic table which are arranged from left to right and seven horizontal rows which are known as periods. Group number Group name Property Group 1 or IA Alkali metals They form strong alkalis with water Group 2 or IIA Alkaline earth They also form alkalis but weaker than group 1 elements metals Group 13 or IIIA Boron family Boron is the first member of this family Group 14 or IVA Carbon family Carbon is the first member of this property Group 15 or VA Nitrogen family This group has non-metals and metalloids Group 16 or VIA Oxygen family They are also known as chalcogens Group 17 or Halogen family The elements of this group form salts.
    [Show full text]
  • Comparison Between Silicon and Carbon*
    OpenStax-CNX module: m32945 1 Comparison Between Silicon and Carbon* Andrew R. Barron This work is produced by OpenStax-CNX and licensed under the Creative Commons Attribution License 3.0 An understanding of the dierences between carbon and silicon is important in understanding the relative chemistry of these Group 14 elements. 1 Size As expected silicon is larger than carbon due to the presence of a second shell: i.e., C = 1s2 2s2 2p2 while Si = 1s2 2s2 2p6 3s2 3p2. A comparison of the relative sizes of carbon and silicon are given in Table 1. Element Atomic radius (Å) Covalent radius sp3 (Å) van der Waal radius (Å) C 0.91 1.11 0.77 Si 1.46 0.76 1.17 Table 1: Atomic, covalent, and van der Waals radii of carbon and silicon. 2 Coordination number Carbon is known to have a coordination number of 2, 3, and 4 in its compounds depending on the hybridiza- tion. A coordination number of 1 can also be considered for CO and CN-. Four-coordinate carbon may be considered to be coordinatively saturated. In contrast, in the absence of overwhelming steric bulk, silicon is observed to have coordination numbers of 3, 4, 5, and 6. Examples of ve and six-coordinate silicon include 2- Si(acac)2Cl and SiF6 , respectively. Coordination numbers of higher than 4 have been ascribed to the use of low-lying d orbitals; however, calculations show these are not signicant. Instead, hypervalent silicon is better described by the formation of 3-center molecular orbitals, e.g., Figure 1.
    [Show full text]
  • Periodic Table(Long Form) Atomic Numbers and Atomic Masses(Nearest Whole Numbers) of Elements
    Periodic Table(Long Form) Atomic Numbers and Atomic masses(nearest whole numbers) of Elements Left portion Right portion H He 1 2 1 4 Li Be B C N O F Ne 3 4 5 6 7 8 9 10 7 11 12 14 16 19 20 Na Mg Al Si P S Cl Ar 11 12 Middle portion 13 14 15 16 17 18 23 24 27 28 31 32 35.5 40 K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 39 40 45 48 51 52 55 56 59 59 63.5 65 70 72.5 75 79 80 84 Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 85.5 88 89 91 93 96 98 101 103 106 108 112 115 119 122 128 127 131 Cs Ba La* Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn 55 56 57 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 133 137 139 178 181 184 186 190 192 195 197 201 204 207 209 209 210 222 Fr Ra Ac** Rf Db Sg Bh Hs Mt Ds Rg Cn Uut Fl Uup Lv Uus Uuo 87 88 89 104 105 106 107 108 109 110 111 112 113 114 115 116 118 223 226 227 Bottom portion *Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu 58 59 60 61 62 63 64 65 66 67 68 69 70 71 140 141 144 147 150 152 157 159 162 165 167 169 173 175 **Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr 90 91 92 93 94 95 96 97 98 99 100 101 102 103 232 231 238 Periodic Table(Long Form) IA IIA IIIA IVA VA VIA VIIA 0 1 2 13 14 15 16 17 18 H He Li Be B C N O F Ne IIIB IVB VB VIB VIIB VIII IB IIB Na Mg 3 4 5 6 7 8 9 10 11 12 Al Si P S Cl Ar K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe Cs Ba La* Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn Ds Rg Cn Uut Fl Uup Lv Uus Uuo Fr Ra Ac** Rf Ha Sg Ns Hs Mt *Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu **Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr Liquids Gases Radioactive natural solid man-made solid PERIODIC CLASSIFICATION Although the world is varied and complex, everything in it, namely air, water, rocks, living tissue and almost infinite number of other objects and materials around us is actually made up of only a limited number of chemical elements.
    [Show full text]
  • The Periodic Table and Periodic Trends”, Chapter 7 from the Book Principles of General Chemistry (Index.Html) (V
    This is “The Periodic Table and Periodic Trends”, chapter 7 from the book Principles of General Chemistry (index.html) (v. 1.0M). This book is licensed under a Creative Commons by-nc-sa 3.0 (http://creativecommons.org/licenses/by-nc-sa/ 3.0/) license. See the license for more details, but that basically means you can share this book as long as you credit the author (but see below), don't make money from it, and do make it available to everyone else under the same terms. This content was accessible as of December 29, 2012, and it was downloaded then by Andy Schmitz (http://lardbucket.org) in an effort to preserve the availability of this book. Normally, the author and publisher would be credited here. However, the publisher has asked for the customary Creative Commons attribution to the original publisher, authors, title, and book URI to be removed. Additionally, per the publisher's request, their name has been removed in some passages. More information is available on this project's attribution page (http://2012books.lardbucket.org/attribution.html?utm_source=header). For more information on the source of this book, or why it is available for free, please see the project's home page (http://2012books.lardbucket.org/). You can browse or download additional books there. i Chapter 7 The Periodic Table and Periodic Trends In Chapter 6 "The Structure of Atoms", we presented the contemporary quantum mechanical model of the atom. In using this model to describe the electronic structures of the elements in order of increasing atomic number, we saw that periodic similarities in electron configuration correlate with periodic similarities in properties, which is the basis for the structure of the periodic table.
    [Show full text]
  • Atomic Radii Dnd Interatomic Distances in Metals'
    542 LINUSPAULING Vol. 69 The values deduced from van der Waals equation than those deduced from van der Waals equation. are, respectively, 2.67 for the critical ratio, 3.38 Summary for the reduced Boyle temperature and 6.75 for the reduced maximum inversion temperature. An equation of state for gases, equation (4) is The average experimental value for the critical proposed, in which all the constants can be calcu- ratio is 3.7 and that for the reduced Boyle lated from the critical values of the temperature temperature is near 2.5. The maximum inver- and pressure in a manner analogous to the evalua- sion temperature has been established for only tion of van der Waals constants. This equation a few substances. The reduced value for ni- is believed to reproduce the behavior of real gases trogeng is 4.93, that for airlo is 4.55. It is seen with a higher degree of accuracy than the van der that the values predicted by equation (4) are Waals equation. In the reduced form (5) it repre- considerably closer to the experimental ones sents an analytical expression of the law of cor- responding states. (9) J. R. Roebuck and H. Osterberg, Phys. Rev., 48,450 (1935). (10) J. R. Roebuck and H. Osterberg, ibid., 43, 60 (1933). RECEIVEDOCTOBER 21, 1946 [CONTRIBUTION FROM THE GATESAND CRELLIN LABORATORIESOF CHEMISTRY, CALIFORNIA INSTITUTE OF TECHNOLOGY, No. 10991 Atomic Radii dnd Interatomic Distances in Metals’ BY LINUSPAULING The problem of the nature of the interatomic mulation of a system of atomic radii which can be farces in the elementary metals and in interme- used for the calculation of interatomic distances tallic compounds and other alloys continues to be in metals and intermetallic compounds and for the puzzling, despite the clarification of some ques- interpretation of observed interatomic distances tions which has been provided by quantum me- in terms of the electronic structure of the crystals.
    [Show full text]
  • Covalent Bond Distance, Radius and Van Der Waals Radius
    Covalent Bond Distance, Radius and van der Waals Radius Covalent bond distance, covalent radius, and van der Waals radius are used to describe the size and distance between atoms. Covalent bond distance refers to the distance between the nuclei of two bonded atoms. Covalent radius is half of the internuclear separation between the nuclei of two single-bonded atoms of the same species (homonuclear). While van der Waals radius is used to define half of the distance between the closest approach of two non-bonded atoms of a given element. Introduction Covalent bond distance, covalent radius, and van der Waals radius are all experimentally determined values that describe the distance around or between atoms. Covalent Bond Distance Covalent bond distance is defined by the internuclear distance between two covalently bonded atoms and is denoted by d. It can be used as a measure of the strength of a bond and can be measured for bonded atoms that have any bond order (not just singly-bonded atoms, as is the case of rcov). Values for Covalent bond distance are determined by X- ray, electron and neutron diffraction, as well as by microwave spectroscopy. Though d is the most commonly measured value, rcov is more commonly used (see next section below). d is measured in picometers (1pm=10-12m) and ångströms (1Å=10-10m). Covalent bond distance can be used as a measure of how tightly two atoms are bonded and is often used to support calculations of bond order. Typically, the higher the bond order, the shorter the Covalent bond distance.
    [Show full text]