粘土矿物分子片段Si6O18H12,（Si5AlO18H12）—和（Si4Al2O18H12）的计算研究

采用最新的量子化学半经验计算方法ＭＮＤＯ－ＰＭ３，对作为粘土矿物结构基元的六元环分子全系进行进行结构与能量的计算，揭示了结构变形的精确程度，并利用能量的差异大小，讨论了几种同分异构体的稳定性。     

新发现的沂蒙矿类质同象系列矿物──K(Ti_5Fe_3Cr_2Mg_2)_(12)O_(19)及Ba(Ti_5Fe_4Mg_2Cr)_(12)O_(19)

在山东蒙阴金伯利岩中，首次发现了沂蒙矿类质同象系列新的富Ti矿物（变）种。理想的晶体化学式可表达为：K（Ti5Fe3Cr2Mg2）12O19（简称K－Ti沂蒙矿）（Ba，K）（Ti5Fe4Mg2Cr）12O19（简称Ba－Ti沂蒙矿）从而与原来确定的沂蒙矿K（Cr5Ti3Fe2Mg2）12O19和钡钛铁铝矿（Ba，K）（Cr4Fe4Ti3Mg）12O19一起构成了金伯利岩中AM12O19磁铁铅矿型矿物的K-Cr、Ba－Cr、K-Ti、Ba-Ti四种端元类型的复杂类质同象系列。新发现的两个矿物（变）种均产出于具叶片状尖晶石出溶体的镁钛铁矿中。根据结构已知的沂蒙矿中原子的占位和配位多面体情况，分析了K－Ti，Ba－Ti沂蒙矿中各原子的占位和配位多面体，认为新发现的两个（变）种在成分上与沂蒙矿和钡钛铁铬矿有明显的区别。根据镁钛铁矿、尖晶石、沂蒙矿新（变）种、钙钛矿之间的相互关系，探讨了它们的形成环境，从而为这类矿物的地幔成因提供了直接证据。     

H_2O-N_2(H_2S、H_2、C_6H_6)体系流体相平衡的精确计算

<正>除了二氧化碳及甲烷外,许多类型的热液流体中还含有一定量的硫化氢、氮气、氢气等挥发分,此外石油天然气中也存在上述无机气体组分及芳香烃,因此准确计算H2O-N2(H2S、H2、C6H6)体系在广阔的温度-压力范围内的气-液相平衡无论是在地质流体研究领域还是在石油天然气工业中都有着重要的应用价值。热力学模型,尤其是状态方程,是计算流体相平衡的有力工具。半经验的立方型状态方程形式简单,普适     

合成锌镁硅云母K_(1.66)Ba_(0.17)(Mg_3Zn_2)(Si_8O_(20))F_4

本文采用高温熔融体热处理结晶的方法合成了含亲硫元素Zn的云母K_(1.66)Ba_(0.17)(Mg_3Zn_2)(Si_8O_20)F_4,其晶胞参数为α=0.525nm,b=0.911nm,c=2.005nm,β=91.28°。这种新型云母的合成在矿物学和地球化学上具有理论意义。     

Zn_3(PhCH=CHCOO)_6(phen)_2·H_2O的纳米晶结构计算及环境属性

Zn3(PhCH=CHCOO)6(phen)2.H2O晶体具有与锰氧化物及锰氢氧化物类似的微结构,在生成环境与晶体化学微结构方面有明显的环境属性,是一种新生环境矿物.为研究其纳米晶结构、最佳纳米尺度和环境矿物属性,在溶液法合成该配合物晶体的基础上,采用纳米晶参数计算方法,对该配合物纳米级微粒的晶胞数、原子数、表面原子数和表面活性随微粒在纳米尺度范围内的变化进行了计算,对比锰氢氧化物结构,发现该配合物晶体活性、表面效应与颗粒尺度有密切关系,内部结构具有鲜明的环境属性.结合晶体颗粒的比表面积与总原子数相对颗粒尺度的变化关系,理论上确定了该颗粒最佳纳米化尺度为138nm,为此类物质纳米晶在环境方面的研究应用奠定了基础.     

丁二酸桥联双核铜Cu(C_3N_2H_4)_2(C_4H_5O_4)_2晶体的超分子结构及形貌特征

用XRD,SEM和TEM研究新型配合物Cu(C3N2H4)2(C4H5O4)2的超分子结构和微观形貌,并对新型晶体的平衡外形进行模拟计算,结果表明:该配合物分子具有丁二酸桥联的双核铜结构,中心铜离子处在2个咪唑和4个丁二酸以单齿配位组成的八面体中心,在ab平面,分子中有十四元大环,环内Cu(1)-Cu(2)原子间距为0.8031nm,C(2)-C(2′)为0.4183nm;在ac平面,沿着[010]方向分子内呈现凹的六边形纳米级孔洞;沿[100]方向分子依靠弱的氢键作用,层状堆积成三维超分子结构。此外,随着丁二酸的碳链沿[001]方向无限延伸,形成以铜离子为交叉中心的带状拓扑构型。SEM观察到晶体表面形成有明显的凹坑,区域呈现层状阶梯,说明晶体在(100)面遵照台阶-扭折模型呈层状生长结晶。TEM微区形貌像显示晶体存在条纹和缺陷结构,整体保持柱状构型,这与模拟的晶体平衡外形呈柱状一致。模拟结果表明晶体最易外显晶面为(100)面,外显比例达41.247%,这与晶体超分子层沿[100]方向通过氢键作用堆积,键作用力较弱密切相关。     

电气石/H_2O_2体系降解Cu(Ⅱ)-EDTA废水的研究

Cu(Ⅱ)-EDTA废水由于其螯合性难以处理.采用电气石/H_2O_2体系进行降解,结果显示废水处理达到较好的效果.COD和Cu~(2+)的去除率与电气石投加量、H_2O_2用量和温度呈正相关性.溶液pH=3时,两者去除率最大.紫外-可见吸收光谱显示,处理后的Cu(Ⅱ)-EDTA被降解为小分子有机物.通过对比电气石反应前后的XRD图谱和红外光谱发现,电气石与EDTA降解中间产物发生络合.反应动力学研究结果表明,电气石/H_2O_2体系降解废水的反应为拟一级反应.     

平均成分为Ca_(0.43)Mn_(0.69)Mg_(0.82)Si_2O_6单斜辉石的出溶关系 X—射线衍射和电子探针分析

一种取自纽约州 Balmat 的辉石,其平均成分是 Ca_(0.43),Mn_(0.69),Mg_(0.82),Si_2O_6;被解释为 p2_1/c 和 c2/c 两种相共存。如晶胞参数 M_1和—O 与 M_2-0键长的平均值与成分所绘制的关系图那样,其精测结构是部分通过研究各个单相的成分获得的。占位情况表明,这两种相是锰透辉石和锰易变辉石(kanoite)。透射电子显微照片揭示,这些相是呈页片状的,共(001),并以此为相间边界,页片宽为2000(?)。单个页片的 x—射线能散分析表明,C2/c 相的平均成分为 Ca_(0.68),Mn_(0.44),Mg_(0.88),Si_2O_6;P_(21)/c 相的平均成分为 Ca_(0.12),Mn_(1.02),Mg_(0.86),Si_2O_6。暗场照片揭示,在 p2_1/c 相中有反相晶畴边界的存在,表明在 Ca—Mn—Mg 辉石体系中,其贫 Ca 相存在着一个 C2/c—P2_1/c相的转变。原地加热实验得到 C2/c—P2_1/c 相的转换温度为330±20℃。通过加热,根据在转换温度前后的反相边界(APB—antiphaseboundary 的编写—编者注)位置的观测,得知 APB 位置基本上不改变,表明 APB′S 的稳定是通过 Ca 的富集或 APB′S 的某些晶体缺陷来实现的。横切页片边界(001)的晶格条纹照片表明,其界面是半连贯或完全连贯的。由于旋节分解或成核作用以及后期缓慢冷却,使得这一作为区域变质相的结构特征与原始的出溶结构相一致。     

Zn_(1.5)PW_(12)O_(40)纳米管催化臭氧氧化苯胺的实验

自行合成了Zn1.5PW12O40纳米管催化剂,在臭氧体系中进行了催化氧化苯胺的实验。通过对苯胺的降解考察了Zn1.5PW12O40纳米管催化剂的催化性能,利用GC/MS对催化反应的途径和机理进行研究,并通过重复实验验证催化剂的回收利用效果。结果发现:在Zn1.5PW12O40的催化下,臭氧对苯胺降解效果有明显的提高,在8 min之内去除率可由单独氧化时的85%提高到99%;其臭氧氧化机理以羟基自由基为主,催化剂的重复利用性较好。     

铝硅酸盐矿物六元环Al避免原则的研究

利用量子化学半经验计算ＰＭ３方法，对硅酸盐矿物结构中重要的六元环体系的各种同分异构体进行了能量差值的计算研究。同实验结果相比，计算的能量差值△Ｅ具有较好的精度，本文用这些△Ｅ值具体讨论了六元环的各种形式中Ａｌ避免原则的正确性和多样性。     

星叶石族矿物的晶体化学

星叶石是碱性岩中分布较广泛的副矿物,成分富含碱金属K、Na及Ti,随其产出的地球化学条件,类质同象代换情况较复杂,形成许多成分异种。本工作之前对其组成和性质都不十分清楚,前人虽进行了一般矿物学研究,但未能确定所属晶系,B.C.索波列夫曾推断星叶石中Ti呈四面体配位,并与硅氧四面体组成复杂构造。     

Some geobarometers involving cordierite in the FeO-Al2O3-SiO2(±H2O) system: refinements,thermodynamic calibration,and applicability in granulite facies rocks

Five geobarometers involving cordierite have been formulated for quantitative pressure sensing in high grade metapelites. The relevant reactions in the FeO-Al₂O₃-SiO₂ (±H₂O) system are based on the assemblages (A) cordierite-garnet-sillimanite-quartz, (B) cordierite-spinel-quartz, (C) cordierite-garnet-spinel-sillimanite, (D) cordierite-garnet-orthopyroxene-quartz and (E) cordierite-orthopyroxene-sillimanite-quartz. Application of the barometric formulations to a large number of granulite grade rocks indicates that the cordierite-garnet-sillimanite-quartz equilibrium is widely applicable and registers pressures which are in good agreement with the “consensus” pressure estimates. The dispersion in the computed P values, expressed as one standard deviation, is within ±1.2 kbar. The geobarometers (B) and (C) also yield pressures which are reasonable and compare well with those computed from equilibrium (A). The estimated pressures from (D) and (E), both involving orthopyroxene, are at variance with these estimates. It has been argued that the discrepancy in pressures obtained from these geobarometers stems from an inadequate knowledge of activity-composition relations and/or errors in input thermodynamic data of aluminous orthopyroxene. The convergence of pressure values estimated from the barometric formulations, especially (A), (B) and (C), implies that the present formulations are more dependable than the existing formulations and are also capable of setting limits on P values in response to varying $$\begin{gathered} {\text{1/2Fe}}_{\text{2}} {\text{Al}}_{\text{4}} {\text{Si}}_{\text{5}} {\text{O}}_{{\text{18}}} \hfill \\ {\text{ = 1/3Fe}}_{\text{3}} {\text{Al}}_{\text{2}} {\text{Si}}_{\text{3}} {\text{O}}_{{\text{12}}} {\text{ + 2/3Al}}_{\text{2}} {\text{SiO}}_{\text{5}} {\text{ + 5/6SiO}}_{\text{2}} {\text{. (A)}} \hfill \\ {\text{1/2Fe}}_{\text{2}} {\text{Al}}_{\text{4}} {\text{Si}}_{\text{5}} {\text{O}}_{{\text{18}}} {\text{ = FeAl}}_{\text{2}} {\text{O}}_{\text{4}} {\text{ + 5/2SiO}}_{\text{2}} {\text{. (B)}} \hfill \\ {\text{Fe}}_{\text{2}} {\text{Al}}_{\text{4}} {\text{Si}}_{\text{5}} {\text{O}}_{{\text{18}}} {\text{ + FeAl}}_{\text{2}} {\text{O}}_{\text{4}} \hfill \\ = {\text{Fe}}_{\text{3}} {\text{Al}}_{\text{2}} {\text{Si}}_{\text{3}} {\text{O}}_{{\text{12}}} {\text{ + 2Al}}_{\text{2}} {\text{SiO}}_{\text{5}} {\text{. (C)}} \hfill \\ {\text{1/2Fe}}_{\text{2}} {\text{Al}}_{\text{4}} {\text{Si}}_{\text{5}} {\text{O}}_{{\text{18}}} {\text{ + Fe}}_{\text{2}} {\text{Si}}_{\text{2}} {\text{O}}_{\text{6}} \hfill \\ = {\text{Fe}}_{\text{3}} {\text{Al}}_{\text{2}} {\text{Si}}_{\text{3}} {\text{O}}_{{\text{12}}} {\text{ + 3/2SiO}}_{\text{2}} .{\text{ (D)}} \hfill \\ {\text{1/2Fe}}_{\text{2}} {\text{Al}}{}_{\text{4}}{\text{Si}}_{\text{5}} {\text{O}}_{{\text{18}}} \hfill \\ = 1/2{\text{Fe}}_{\text{2}} {\text{Si}}_{\text{2}} {\text{O}}_{\text{6}} {\text{ + Al}}_{\text{2}} {\text{SiO}}_{\text{5}} {\text{ + 1/2SiO}}_{\text{2}} .{\text{ (E)}} \hfill \\ \end{gathered}$$ . The present communication addresses the calibration, applicability and reliability of these barometers with reference to granulite facies metapelites.     

Batisite,Na2BaTi2(Si4O12)O2, from Inagli massif,Aldan, Russia: crystal-structure refinement and high-temperature X-ray diffraction study

Mineralogy and Petrology - The crystal structure of batisite, Na2BaTi2 (Si4O12)O2, from the Inagli massif (Aldan, Yakutia, Russia) was refined to R 1&nbsp;=&nbsp;0.032 for 1449 unique...     

太阳原始星云原子团簇的初步研究

选用Ａｌｌｅｎｄｅ和宁强两块ＣＶ３陨石，在分子团簇串级飞行时间质谱装置上。用激光溅射模拟太阳原始星云在高能环境下的Ｓｉ－０，Ｆｅ－０和Ｍｇ－０原子团簇的形成和分布，对模拟过程所产上的原子团簇系列的结构和稳定性，以及可能的天体化学意义进行了初步探讨。     

A single-crystal neutron and X-ray diffraction study of pezzottaite, Cs(Be2Li)Al2Si6O18

The chemical composition and the crystal structure of pezzottaite [ideal composition Cs(Be₂Li)Al₂Si₆O₁₈; space group: ${\it{R}} \overline{\text{3}} $ c, a?=?15.9615(6) ?, c?=?27.8568(9) ?] from the type locality in Ambatovita (central Madagascar) were investigated by electron microprobe analysis in wavelength dispersive mode, thermo-gravimetric analysis, Fourier-transform infrared spectroscopy, single-crystal X-ray (at 298?K) and neutron (at 2.3?K) diffraction. The average chemical formula of the sample of pezzottaite resulted ^Cs1,Cs2(Cs_0.565Rb_0.027K_0.017)_Σ0.600 ^Na1,Na2(Na_0.101Ca_0.024)_Σ0.125Be_2.078Li_0.922 ^Al1,Al2(Mg_0.002Mn_0.002Fe_0.003Al_1.978)_Σ1.985 ^Si1,Si2,Si3(Al_0.056Si_5.944)_Σ6O₁₈·0.27H₂O. The (unpolarized) IR spectrum over the region 3,800–600?cm^?1 was collected and a comparison with the absorption bands found in beryl carried out. In particular, two-weak absorption bands ascribable to the fundamental H₂O stretching vibrations (i.e. 3,591 and 3,545?cm^?1) were observed, despite the mineral being nominally anhydrous. The X-ray and neutron structure refinements showed: (a) a non-significant presence of aluminium, beryllium or lithium at the Si1, Si2 and Si3 sites, (b) the absence (at a significant level) of lithium at the octahedral Al1, Al2 and Al3 sites and (c) a partial lithium/beryllium disordering between tetrahedral Be and Li sites.     

Ab initio Hartree–Fock study and charge density analysis of beryl (Al4Be6Si12O36)

 An ab initio Hartree–Fock calculation on beryl structure has been performed and the wave function has been used for an analysis of the electron density. The equilibrium geometry, determined by minimizing the energy with respect to cell parameters and fractional coordinates, is in good agreement with structural experimental measurements; small differences in length between the various Si–O bonds of the structure are well reproduced by the calculation. The two non-equivalent oxygen atoms (O1 and O2) of beryl show different electron distributions. In particular, the valence shell charge concentration (VSCC) of O1 (the bridge between two Si ions) has a torus-like shape, showing a bulge on the external side of the Si–O–Si angle and a thinning on the internal side of it; by contrast O2 has two lone pairs which are approximately located on the line for O2, normal to the plane passing, on average, through the atoms O2, Si, Be and Al. The electron density of each oxygen is strongly polarized toward the Si ions and much less polarized towards the other cations. Such features of the VSCC of the oxygens can be recast in terms of the valence bond theory, to explain the observed differences in bond lengths. By calculating the potential inside the channels of the beryl structure, predictions could be made about the positions occupied by alkali cations, which are often found in natural minerals belonging to the beryl group: results agree in general with experimental findings, but foresee a shift of such cations off the central positions located on the six fold symmetry axis. Additionally, calculations of position and orientation of H₂O inside the channel, in the alkali-free beryl, locate the molecule close to the basal plane, with the H⋯H axis parallel to [001] or oriented at 40^∘ from it. Received: 12 December 2001 / Accepted: 6 April 2002     

Compressibility and structure behaviour of maruyamaite (K-tourmaline) from the Kokchetav massif at high pressure up to 20 GPa

Mineralogy and Petrology - The structural behaviour of maruyamaite (K-dominant tourmaline) X(K0.54Na0.28Ca0.19)Y(Mg1.3Al1.17Fe0.39Ti0.14)Z(Al5Mg)[Si5.95Al0.05O18](BO3)3V,W[O1.69(OH)2.31] from the...     

Alumovesuvianite,Ca19Al(Al,Mg)12Si18O69(OH)9, a new vesuvianite-group member from the Jeffrey mine,asbestos, Estrie region,Québec,Canada

Mineralogy and Petrology - Alumovesuvianite (IMA 2016–014), ideally Ca19Al(Al,Mg)12Si18O69(OH)9, is a new vesuvianite-group member found in the rodingite zone at the contact of a gabbroid...     

中国金伯利岩地球化学

本文利用了100多个金伯利岩的主要元素及微量元素分析结果,用Si/Mg、C.l——(SiO_2+Al_2O_3+Na_2O)/(MgO+2K_2O)、Mg/(Mg+Fe)比值及SiO_2、Al_2O_3及Na_2O含量研究了金伯利岩的混染程度。结果表明,绝大部分金伯利岩受到了混染作用的影响,它们的成分实际上不能代表形成这些岩石的岩浆的成分。金伯利岩的Al_2O_3和Na_2O的含量比其他碱性超基性及基性岩石的Al_2O_3和Na_2O含量低得多。含金刚石的金伯利岩比不含金刚石的金伯利岩的MgO、(Cr_2O_3+NiO)高,而TiO_2+Al_2O_3+Na_2O+K_2O+P_2O_5低。 我国金伯利岩中Cr-Al,Ni-Co,Ni-Cr,Ni-V,Sc-Ti,Zn-Ti,Ba-Sr,Zr-Hf,Nb-Ta,U-Th,K-Rb呈正相关关系。