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1.
Satyasree Rajendrakumar Anuja Surampudi Venkata Sai Durga Jagadeesh Babu Nanubolu Sridhar Balasubramanian 《Acta Crystallographica. Section C, Structural Chemistry》2020,76(2):193-200
Thalassemia is a genetic blood disorder requiring life‐long blood transfusions. This process often results in iron overload and can be treated by an iron‐chelating agent, like deferiprone (3‐hydroxy‐1,2‐dimethylpyridin‐4‐one), C7H9NO2, in an oral formulation. The first crystal structure of deferiprone, (Ia), was reported in 1988 [Nelson et al. (1988). Can. J. Chem. 66 , 123–131]. In the present study, two novel polymorphic forms, (Ib) and (Ic), of deferiprone were identified concomitantly with polymorph (Ia) during the crystallization experiments. Polymorph (Ia) was redetermined at low temperature for comparison of the structural features and lattice energy values with polymorphs (Ib) and (Ic). Polymorph (Ia) crystallized in the orthorhombic space group Pbca, whereas both polymorphs (Ib) and (Ic) crystallized in the monoclinic space group P21/c. The asymmetric units of (Ia) and (Ib) contain one deferiprone molecule, while polymorph (Ic) has three crystallographically independent molecules (A, B and C). All three polymorphs have similar hydrogen‐bonding features, such as an R22(10) dimer formed by O—H…O hydrogen bonds, an R43(20) tetramer formed by C—H…O hydrogen bonds and π–π interactions, but the polymorphs differ in their molecular arrangements in the solid state and are classified as packing polymorphs. O—H…O and C—H…O hydrogen bonds lead to the formation of two‐dimensional hydrogen‐bonded parallel sheets which are interlinked by π–π stacking interactions. In the three‐dimensional crystal packing, the deferiprone molecules were aggregated as corrugated sheets in polymorphs (Ia) and (Ic), whereas in polymorph (Ib), they were aggregated as a square‐grid network. The characteristic crystalline peaks of polymorphs (Ia), (Ib) and (Ic) were established through powder X‐ray diffraction analysis. The Rietveld analysis was also performed to estimate the contribution of the polymorphs to the bulk material. 相似文献
2.
Two novel trinuclear cluster-based coordination polymers {[M3(dip)(AcO)6]·(X)}n (1, M = Cu, X = CH3OH; 2, M = Co, X = 2H2O) (dip is 2,6-Di-imidazol-1-yl-pyridine), have been synthesised and structurally determined by single crystal X-ray diffraction, element analysis. Crystallographic unit of 1 consists of three Cu(II), six acetic ions, one dip ligand and one methanol molecule, which formed 1D chain through acetic bridges. The 1D chain further constructed 2-D network through dip ligand bridge which formed 3-D network through π···π interaction. Crystallographic unit of 2 consists of three Co(II), six acetic ions, one dip ligand and two water molecules. The trinuclear unit further formed a dimmer through dip ligand bridge which constructed 1-D through dip ligand bridge. The 1D chain further constructed 2-D network through π···π interaction. IR and UV–vis spectrum properties of 1 and 2 were studied. In addition, Hirshfeld surface analysis was also studied for 1. 相似文献
3.
《Acta Crystallographica. Section C, Structural Chemistry》2017,73(1):20-27
The syntheses of new myo‐inositol derivatives have received much attention due to their important biological activities. 1,2‐O‐Cyclohexylidene‐myo‐inositol is an important intermediate formed during the syntheses of certain myo‐inositol derivatives. We report herein the crystal structure of 1,2‐O‐cyclohexylidene‐myo‐inositol dihydrate, C12H20O6·2H2O, which is an intermediate formed during the syntheses of myo‐inositol phosphate derivatives, to demonstrate the participation of water molecules and hydroxy groups in the formation of several intermolecular O—H…O interactions, and to determine a low‐energy conformation. The title myo‐inositol derivative crystallizes with two water molecules in the asymmetric unit in the space group C 2/c , with Z = 8. The water molecules facilitate the formation of an extensive O—H…O hydrogen‐bonding network that assists in the formation of a dense crystal packing. Furthermore, geometrical optimization and frequency analysis was carried out using density functional theory (DFT) calculations with B3LYP hybrid functionals and 6‐31G(d), 6‐31G(d,p) and 6‐311G(d,p) basis sets. The theoretical and experimental structures were found to be very similar, with only slight deviations. The intermolecular interactions were quantitatively analysed using Hirshfeld surface analysis and 2D (two‐dimensional) fingerplot plots, and the total lattice energy was calculated. 相似文献
4.
Takjoo Reza Takjoo Rozita Yazdanbakhsh Mohammad Aghaei kaju Amir Chen Yaguang 《中国化学》2010,28(2):221-228
A new mixed ligand palladium(II) complex with bidentate NS‐donor chelate, [PdCl(PPh3)L] (L: S‐allyl β‐N‐(benzylidene)dithiocarbazate), has been prepared and characterized using single crystal X‐ray diffraction and spectroscopic (electronic, IR, 1H NMR and 13C NMR) techniques. The shorter Pd? P bond distance, 2.255(7) Å, than the sum of the single bond radii for palladium and phosphorus (2.41 Å), showed partial double bond character. Visualizing and exploring the crystal structure using Hirshfeld surface analysis showed the presence of π··· π, N··· π, C? H··· π, Cl···H and weak C? H···S interactions as most important intermolecular interactions in the crystal lattice, which are responsible to extension of the supramolecular network of the compound and stabilization of the crystal structure. 相似文献
5.
An organic-inorganic hybrid based on α-Keggin-typed [BW12O40]5- anionic cluster, [Co(BⅡM)3]2H[BW12O40]·7H2O(BⅡM = 2,2′-biimidazole), was hydrothermally synthesized and structurally characterized by thermogravimetric analysis, IR and UV spectra. The title compound crystallizes in monoclinic, space group P21/n with a = 12.3490(10), b = 33.270(3), c = 18.9660(16) β = 105.9950(10)°, V = 7490.5(11) 3, C36H50BCo2N24O47W12, Mr = 3905.80, Dc = 3.451g/cm3, μ(MoKα) = 18.886 mm-1, F(000) = 6972, Z = 4, S = 1.004, the final R = 0.0404 and wR = 0.0914 for 14683 observed reflections(I 2σ(I)). The compound consists of two isolated [Co(BⅡM)3]2+ cations and one [BW12O40]5- anion, in which each Co2+ ion is coordinated by six N atoms from three BⅡM ligands displaying a regular CoN6 octahedron. These components are finally linked together via N–H···O(polyoxometalate and water) hydrogen bonds into a two-dimensional framework. Full investigation of the intermolecular interactions by Hirshfeld surface and fingerprint plots clearly indicates that there are rare W–Oterminal···πimidazole ring interactions which cooperate with the classical N–H···O hydrogen bonds to stabilize the structural packing. 相似文献
6.
A cocrystal based on 1,3-di(4-pyridyl)propane and 3-((4′-carboxybenzyl)oxy)benzoic acid,C13H14N2·C15H12O5,has been synthesized and characterized by single-crystal X-ray diffraction.The compound crystallizes in monoclinic,space group P21 /c with a = 11.639(4),b = 9.808(3),c = 20.854(6),β = 91.242(7)°,V = 2380.0(13)3,C28H26N2O5,Mr = 470.51,Dc = 1.313 g/cm3,μ(MoKα) = 0.091 mm-1,F(000) = 992,Z = 4,the final R = 0.0677 and wR = 0.1477 for 4175 observed reflections(I > 2σ(I)).Intermolecular N H···O hydrogen bonds link two kinds of components into a one-dimensional chain in [10-1] direction and adjacent chains are further arranged into a two-dimensional network by π···π and C H···π interactions.Investigation of intermolecular interactions and crystal packing via Hirshfeld surface analysis reveals that the close contacts are mainly focused on weak interactions.The theoretical investigations with HF/6-31G(d) method were performed,and its stability,frontier molecular orbital composition and Mulliken charge distribution were also discussed. 相似文献
7.
Diorganotin (IV) complexes SnR2X2 (R = Me, Ph; X = Cl, NCS) form a series of versatile complexes when react with bidentate substituted pyridyl ligands. The reaction of dimethyltin dichloride with 5,5′‐dimethyl‐2,2′‐bipyridine (5,5′‐Me2bpy) resulted in the formation of [SnMe2Cl2(5,5′‐Me2bpy)] ( 1 ). Moreover, the reaction of SnMe2(NSC)2 with 4,4′‐di‐tert‐butyl‐2,2′‐bipyridine (bu2bpy), 1,10‐phenanthroline (phen) and 4,7‐diphenyl‐1,10‐phenanthroline (bphen) affords the hexa‐coordinated complexes [SnMe2(NCS)2(bu2bpy)] ( 2 ), [SnMe2(NCS)2(phen)] ( 3 ) and [SnMe2(NCS)2(bphen)] ( 4 ), respectively. The resulting complexes have been characterized using elemental analysis, IR, multinuclear NMR (1H, 13C, 119Sn) and DEPT‐135° NMR spectroscopy. On the other hand, the reaction of diphenyltin dichloride with 2,2′‐biquinoline (biq) and 4,7‐phenantroline (4,7‐phen) led to the formation of polymeric complexes of [SnPh2Cl2(4,7‐phen)]n ( 5 ) and [SnPh2Cl2(biq)]n ( 6 ). The NMR spectra, however, reveal the ligand lability in solution and suggest a coordination number of 5 . The X‐ray crystal structures of complexes [SnMe2Cl2(5,5′‐Me2bpy)] ( 1 ), [SnMe2(NCS)2(bu2bpy)] ( 2 ) and [SnMe2(NCS)2(bphen)] ( 4 ) have been determined which reveal that the geometry around the tin atom is distorted octahedral with trans‐[SnMe2] configuration. Interestingly, the crystal structure of (H2biq)2[SnPh2Cl4]?2CHCl3 ( 7 ) was characterized by X‐ray crystallography from a chloroform solution of [SnPh2Cl2(biq)]n ( 6 ) indicating the formation of doubly protonated [H2biq]+ and [Ph2SnCl4]2? which are stabilized by a network of hydrogen bonds with a feature of trans‐[SnPh2]. The 3D Hirshfeld surface analysis and 2D fingerprint maps were used for quantitative mapping out of the intermolecular interactions for 1 , 2 , 4 and 7 which show the presence of π‐π and hydrogen bonding interactions which are associated between donor and acceptor atoms (N, S, Cl) in the solid state. 相似文献
8.
An organic-inorganic hybrid based on a-Keggin-typed [BWI2040]5- anionic cluster, [Co(BIIM)3]2H[BWx2040]'7H20 (BIIM = 2,2"-biimidazole), was hydrothermally synthesized and structurally characterized by thermogravimetric analysis, IR and UV spectra. The title compound crystallizes in monoclinic, space group P21/n with a = 12.3490(10), b = 33.270(3), c = 18.9660(16) A, β = 105.9950(10)°, V= 7490.5(11) A3, C36HsoBCo2N24047W12, Mr = 3905.80, Dc = 3.45 l g/cm3, μ(MoKa) = 18.886 rnm-1, F(000) = 6972, Z = 4, S = 1.004, the final R = 0.0404 and wR = 0.0914 for 14683 observed reflections (1 〉 2tr(/)). The compound consists of two isolated [Co(BIIM)3]2+ cations and one [BW12040]5 anion, in which each Co2+ ion is coordinated by six N atoms from three BIIM ligands displaying a regular CoN6 octahedron. These components are finally linked together via N-H...O(polyoxometalate and wate) hydrogen bonds into a two-dimensional framework. Full investigation of the intermolecular interactions by Hirshfeld surface and fingerprint plots clearly indicates that there are rare W--Oterminal···πimidazole ring interactions which cooperate with the classical N-H···O hydrogen bonds to stabilize the structural packing. 相似文献
9.
10.
Christina A. Capacci-Daniel Jeffery A. Bertke Shoaleh Dehghan Rupa Hiremath-Darji Jennifer A. Swift 《Acta Crystallographica. Section C, Structural Chemistry》2016,72(9):692-696
Hydrogen bonding between urea functionalities is a common structural motif employed in crystal‐engineering studies. Crystallization of 1,3‐bis(3‐fluorophenyl)urea, C13H10F2N2O, from many solvents yielded concomitant mixtures of at least two polymorphs. In the monoclinic form, one‐dimensional chains of hydrogen‐bonded urea molecules align in an antiparallel orientation, as is typical of many diphenylureas. In the orthorhombic form, one‐dimensional chains of hydrogen‐bonded urea molecules have a parallel orientation rarely observed in symmetrically substituted diphenylureas. 相似文献
11.
Ali Harchani Damian Trzybiski Sylwia Pawldzio Krzysztof Wo
niak Amor Haddad 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(2):128-134
The crystal structure and the results of theoretical calculations for the new organoarsenate salt o‐anisidinium dihydroarsenate (systematic name: 2‐methoxyanilinium dihydrogen arsenate), C7H10NO+·H2AsO4?, are reported. The salt, crystallizing in the triclinic space group P, was synthesized using a solution method and was characterized by single‐crystal X‐ray diffraction analysis. It possesses a layered supramolecular architecture in the crystal. The intermolecular interactions were studied using Hirshfeld surface analysis which confirmed that hydrogen bonds and H…H contacts play dominant roles in the crystal structure of the investigated system. An analysis of the electronic structure and molecular modelling using charge distribution confirms the good electrophilic reactivity of the title compound. 相似文献
12.
Amir Hossein Alamdar Mehrdad Pourayoubi Anahid Saneei Michal Duek Monika Ku
erkov Margarida S. Henriques 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(9):824-833
Hirshfeld surfaces and two‐dimensional fingerprint plots are used to analyse the intermolecular interactions in two new phosphorothioic triamide structures, namely N,N′,N′′‐tris(3,4‐dimethylphenyl)phosphorothioic triamide acetonitrile hemisolvate, P(S)[NHC6H3‐3,4‐(CH3)2]3·0.5CH3CN or C24H30N3PS·0.5CH3CN, (I), and N,N′,N′′‐tris(4‐methylphenyl)phosphorothioic triamide–3‐methylpiperidinium chloride (1/1), P(S)[NHC6H4(4‐CH3)]3·[3‐CH3‐C5H9NH2]+·Cl− or C21H24N3PS·C6H14N+·Cl−, (II). The asymmetric unit of (I) consists of two independent phosphorothioic triamide molecules and one acetonitrile solvent molecule, whereas for (II), the asymmetric unit is composed of three components (molecule, cation and anion). In the structure of (I), the different components are organized into a six‐molecule aggregate through N—H...S and N—H...N hydrogen bonds. The components of (II) are aggregated into a two‐dimensional array through N—H...S and N—H...Cl hydrogen bonds. Moreover, interesting features of packing arise in this structure due to the presence of a double hydrogen‐bond acceptor (the S atom of the phosphorothioic triamide molecule) and of a double hydrogen‐bond donor (the N—H unit of the cation). For both (I) and (II), the full fingerprint plot of each component is asymmetric as a consequence of the presence of three fragments. These analyses reveal that H...H interactions [67.7 and 64.3% for the two symmetry‐independent phosphorothioic triamide molecules of (I), 30.7% for the acetonitrile solvent of (I), 63.8% in the phosphorothioic triamide molecule of (II) and 62.9% in the 3‐methylpiperidinium cation of (II)] outnumber the other contacts for all the components in both structures, except for the chloride anion of (II), which only receives the Cl...H contact. The phosphorothioic triamide molecules of both structures include unsaturated C atoms, thus presenting C...H/H...C interactions: 17.6 and 21% for the two symmetry‐independent phosphorothioic triamide molecules in (I), and 22.7% for the phosphorothioic triamide molecule of (II). Furthermore, the N—H...S hydrogen bonds in both (I) and (II), and the N—H...Cl hydrogen bonds in (II), are the most prominent interactions, appearing as large red spots on the Hirshfeld surface maps. The N...H/H...N contacts in structure (I) are considerable, whereas for (II), they give a negligible contribution to the total interactions in the system. 相似文献
13.
通过硝酸镍与卤代希夫碱在甲醇溶液中反应,合成了2个Ni(Ⅱ)希夫碱配合物[Ni(3,5-Cl-salcy)](1)和[Ni(3-Cl-salcy)](2),(3,5-Cl-salcyH2=N,N′-(±)-双(3,5-二氯水杨基)-1,2-环己二胺; 3-Cl-salcyH2=N,N′-(±)-双(3-氯水杨基)-1,2-环己二胺)。通过X射线衍射测定了2个配合物的结构。结构分析表明2个配合物的基本单元均为Ni(Ⅱ)离子通过与希夫碱配体的[N2O2]原子配位构成相似的平面型单核配合物。Platon软件分析表明配合物1中并不存在任何氢键,配合物2也仅存在非经典氢键。通过Hirshfeld表面分析法对2个配合物晶体结构中弱交换作用的分析结果表明,虽然卤原子构成的氢键相对较弱,但是C-H…X在稳定三维超分子晶体结构中起着非常重要的作用;此外,通过2个配合物的对比发现,配体中卤原子数量的不同对于晶体中弱交换作用的占比可以起到非常重要的影响。 相似文献
14.
One novel adduct based on aminopyridinium and biphenyl-2,4′-dicarboxylate, C5H7N2+·C14H9O4-, has been synthesized and characterized by X-ray structural study. The compound crystallizes in trigonal, space group P32 with a = 9.2886(16), b = 9.2886(16), c = 16.746(6) , γ = 120°, V = 1251.2(5) 3, C19H16N2O4, Mr = 336.34, Dc = 1.339 g/cm3, μ(MoKα) = 0.095 mm-1, F(000) = 528, Z = 3, the final R = 0.0438 and wR = 0.1119 for 3097 observed reflections (Ⅰ > 2σ(Ⅰ)). Its electronic structure was calculated at the RHF/6-31G(d) level and a detailed analysis of intermolecular interactions was used by Hirshfeld surface and fingerprint plot. Intermolecular N-H…O hydrogen bonds link two components generating R22(8) rings which are linked into three one-dimensional chains in the [100], [010] and [110] directions, and these chains are finally arranged into a three-dimensional framework by hydrogen bonds. Investigation of intermolecular interactions via Hirshfeld surface analysis reveals that the close contacts are mainly associated with the classical hydrogen bonding interactions. The HOMO-LUMO energy gap of the compound indicates a higher kinetic stability. 相似文献
15.
Banafsheh Vahdani Alviri Mehrdad Pourayoubi Abolghasem Farhadipour Manpreet Kaur Jerry P. Jasinski 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(10):1424-1433
The asymmetric unit of O,O′‐dimethyl [(2,3,4,5,6‐pentafluorophenyl)hydrazinyl]phosphonate, C8H8F5N2O3P, is composed of two symmetry‐independent molecules with significant differences in the orientations of the C6F5 and OMe groups. In the crystal structure, a one‐dimensional assembly is mediated from classical N—H…O hydrogen bonds, which includes R22(8), D(2) and some higher‐order graph‐set motifs. By also considering weak C—H…O=P and C—H…O—C intermolecular interactions, a two‐dimensional network extends along the ab plane. The strengths of the hydrogen bonds were evaluated using quantum chemical calculations with the GAUSSIAN09 software package at the B3LYP/6‐311G(d,p) level of theory. The LP(O) to σ*(NH) and σ*(CH) charge‐transfer interactions were examined according to second‐order perturbation theory in natural bond orbital (NBO) methodology. The hydrogen‐bonded clusters of molecules, including N—H…O and C—H…O interactions, were constructed as input files for the calculations and the strengths of the hydrogen bonds are as follows: N—H…O [R22(8)] > N—H…O [D(2)] > C—H…O. The decomposed fingerprint plots show that the contribution portions of the F…H/H…F contacts in both molecules are the largest. 相似文献
16.
利用配体 5-(二甲基氨基)间苯二甲酸(H2dia)和咪唑(mdz)分别与锌(Ⅱ)和铜(Ⅱ)金属盐反应,制备了 3 例过渡金属配合物[Zn(dia)(mdz)2]·2H2O (1)、[Cu(dia)(mdz)2(DMF)] (2)和[Cu(dia)(mdz)2]·H2O (3)。利用单晶 X射线衍射、元素分析、红外光谱、热重和Hirshfeld表面分析对其进行了结构表征。结果表明配合物1和2为一维线状链,1中每个四配位的Zn(Ⅱ)处于变形四面体中心,2中Cu(Ⅱ)中心拥有五配位的三角双锥几何构型。改变合成溶剂条件得到锯齿形一维链状配合物3,其四配位Cu(Ⅱ)中心展现出对称平面四边形构型。上述结果说明,金属离子几何构型以及合成溶剂可能对配合物结构具有重要影响。丰富的分子间氢键帮助3例配合物形成稳定的三维超分子结构。热重分析表明,3例配合物均具有良好的热稳定性。固体荧光分析表明配合物1具有较强荧光性,而配合物2和3荧光强度均远低于配体。 相似文献
17.
利用配体 5-(二甲基氨基)间苯二甲酸(H2dia)和咪唑(mdz)分别与锌(Ⅱ)和铜(Ⅱ)金属盐反应,制备了 3 例过渡金属配合物[Zn(dia)(mdz)2]·2H2O (1)、[Cu(dia)(mdz)2(DMF)] (2)和[Cu(dia)(mdz)2]·H2O (3)。利用单晶 X射线衍射、元素分析、红外光谱、热重和Hirshfeld表面分析对其进行了结构表征。结果表明配合物1和2为一维线状链,1中每个四配位的Zn(Ⅱ)处于变形四面体中心,2中Cu(Ⅱ)中心拥有五配位的三角双锥几何构型。改变合成溶剂条件得到锯齿形一维链状配合物3,其四配位Cu(Ⅱ)中心展现出对称平面四边形构型。上述结果说明,金属离子几何构型以及合成溶剂可能对配合物结构具有重要影响。丰富的分子间氢键帮助3例配合物形成稳定的三维超分子结构。热重分析表明,3例配合物均具有良好的热稳定性。固体荧光分析表明配合物1具有较强荧光性,而配合物2和3荧光强度均远低于配体。 相似文献
18.
《Acta Crystallographica. Section C, Structural Chemistry》2018,74(6):683-689
The simultaneous crystallization of different polymorphs, i.e. concomitant polymorphism, is a phenomenon which, when properly recognized and studied, can provide useful information for a variety of disciplines. It is rare for ruthenium complexes, although it has been observed. In the synthesis of the ruthenium(II) complex chlorido(η6‐p‐cymene)(dimethyl 2,2′‐bypyridine‐4,5‐dicarboxylate‐κ2N,N′)ruthenium(II) hexafluoridophosphate, [RuCl(C10H14)(C14H12N2O4)]PF6, concomitant polymorphs were crystallized under the same conditions. The colour of both crystals was orange, but the shapes, as well as the orientation of the p‐cymene and methoxycarbonyl groups, were different. The crystal structures of both isomers show approximately the same bond lengths. In the asymmetric unit, there is one cation and one anion. Due to the absence of strong hydrogen bonds, only weak intermolecular interactions were observed. The Hirshfeld surface and two‐dimensional fingerprint plots of both isomers satisfactorily explain the difference in the melting points. 相似文献
19.
Hazel A. Sparkes Henry J. Sage Dmitry S. Yufit 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(9):872-875
The crystal structures of 1,2‐dimethyl‐3‐nitrobenzene, C8H9NO2, and 2,4‐dimethyl‐1‐nitrobenzene, C8H9NO2, which are liquids at room temperature, have been obtained through in‐situ cryocrystallization. Weak C—H...O and also π–π interactions are present in both crystal structures. 相似文献
20.
Anna Puckowska Magdalena Gawel Marlena Komorowska Pawel Drozdzal Aleksandra Arning Damian Pawelski Krzysztof Brzezinski Marta E. Plonska-Brzezinska 《Molecules (Basel, Switzerland)》2022,27(6)
Derivatives based on pyridine-2-6- and furan-2,5-dicarboxamide scaffolds reveal numerous chemical properties and biological activities. This fact makes them an exciting research topic in supramolecular and coordination chemistry and in discovering new pharmacologically-active compounds. This work aimed to obtain a series of symmetrical pyridine-2-6- and furan-2,5-dicarboxamides through a condensation reaction of the appropriate acyl chlorides and aromatic amides. Successful syntheses were confirmed with NMR spectroscopy. We solved their crystal structures for seven compounds; two pyridine and five furan derivatives. Based on our crystallographic studies, we were able to indicate supramolecular features of the crystals under investigation. Additionally, Hirshfeld surface analysis allowed us to calculate a distribution of intermolecular contacts in the dicarboxamide crystals. 相似文献