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Are the results of the study of the growth of seed progeny of Apple obtained by hybridization. Studies were conducted in the Botanical Garden of them. Vs.M. Krutovsky with trees varieties of Sharopai (winter maturation, macrocarpa), Antipashaljnoe (winter maturation, with fruits burgundy coloured), Arcad stakanchaty, Golden thorn, Papirovka (earlymaturing, high yield), White naliv (macrocarpa, early maturation). The purpose of the research: selection of parental pairs for hybridization, selection of sibs and halfsibs on elements of early diagnosis, which correlated with macrocarpa and fruits burgundy coloured, indicating that increased plant resistance to disease, pests. The selection of trees for hybridization was carried out by taking into account the following criteria: late blooming flowers, early ripening; increased productivity, macrocarpa, fruits burgundy coloured. Were measured height, diameter of the inner barrel near the root, leaf surface area of seedlings. Was installed the manifestation of colouring of the fruit in the offspring on colouring of leaves, estimating the frequency distribution of the Pearson χ2 criterion. Two-years families made comparison of direct and reverse hybridization parental couples as well as families of the same parent plants with free pollination, by height, diameter of the inner barrel and the leaf surface area. The level of variability in two-years sibs and halfsibs families in height, diameter of the inner barrel -from low to medium, leaf surface area - from medium to high. In the experience, where as the parent trees were taken of Sharopai, the greatest indicators of sibs by height and diameter of the inner barrel were after hybridization with tree № 54 varieties of Papirovka, leaf surface area - tree № 4 of Arcad stakanchaty. Comparison of biometric indicators sibs from direct and reverse hybridization was inconsequential. Families of free crossing of varieties of trees Sharopai in most variants had lower values than the family sibs. Experience with using hybridization trees varieties Antipashaljnoe the greatest performance (height, diameter and leaf surface area) were sibs in hybridization with tree 6 Golden thorn. Indicators were lower when the reverse hybridization trees. Differences between families amounted to 12.1% in height, diameter of the inner barrel - up to 7.3%, leaf surface area -up to 39.7%. The largest biometric indicators were obtained by reverse hybridization tree 76A Antipashaljnoe and 63 Papirovka tree. On the square sheet were select the sibs of 54A White naliv x 52 Antipashaljnoe and halfsibs tree 54A White naliv. The distribution of sibs and halfsibs of colouring of leaves in options with using trees varieties Antipashaljnoe are analyzed: when direct hybridization prevailed burgundy colouring of leaves (up to 64%), with the reverse -the percentage of plants with burgundy colour does not exceed 37%.

Botanical gardens and arboreta of higher educational institutions of Federal agency on education of Ministry of education and science of Russian Federation

The X-ray absorption spectra of aqueous ammonia and ammonium are computed using a combination of coupled cluster singles and doubles (CCSD) with different quantum mechanical and molecular mechanical embedding schemes. Specifically, we compare frozen Hartree-Fock (HF) density embedding, polarizable embedding (PE), and polarizable density embedding (PDE). Integrating CCSD with frozen HF density embedding is possible within the CC-in-HF framework, which circumvents the conventional system-size limitations of standard coupled cluster methods. We reveal similarities between PDE and frozen HF density descriptions, while PE spectra differ significantly. By including approximate triple excitations, we also investigate the effect of improving the electronic structure theory. The spectra computed using this approach show an improved intensity ratio compared to CCSD-in-HF. Charge transfer analysis of the excitations shows the local character of the pre-edge and main-edge, while the post-edge is formed by excitations delocalized over the first solvation shell and beyond.

X-ray absorption (XA) spectroscopy is an essential experimental tool to investigate the local structure of liquid water. Interpretation of the experiment poses a significant challenge and requires a quantitative theoretical description. High-quality theoretical XA spectra require reliable molecular dynamics simulations and accurate electronic structure calculations. Here, we present the first successful application of coupled cluster theory to model the XA spectrum of liquid water. We overcome the computational limitations on system size by employing a multilevel coupled cluster framework for large molecular systems. Excellent agreement with the experimental spectrum is achieved by including triple excitations in the wave function and using molecular structures from state-of-the-art path-integral molecular dynamics. We demonstrate that an accurate description of the electronic structure within the first solvation shell is sufficient to successfully model the XA spectrum of liquid water within the multilevel framework. Furthermore, we present a rigorous charge transfer analysis of the XA spectrum, which is reliable due to the accuracy and robustness of the electronic structure methodology. This analysis aligns with previous studies regarding the character of the prominent features of the XA spectrum of liquid water., (© 2024. The Author(s).)

We recently introduced the particle-breaking restricted Hartree-Fock (PBRHF) model, a mean-field approach to address the fractional charging of molecules when they interact with an electronic environment. In this paper, we present an extension of the model referred to as particle-breaking unrestricted Hartree-Fock (PBUHF). The unrestricted formulation contains odd-electron states necessary for a realistic description of fractional charging. Within the PBUHF parametrization, we use two-body operators as they yield convenient operator transformations. However, two-body operators can change only the particle number by two. Therefore, we include noninteracting zero-energy bath orbitals to generate a linear combination of even and odd electron states. Depending on whether the occupied or virtual orbitals of a molecule interact with the environment, the average number of electrons is either decreased or increased. Without interaction, PBUHF reduces to the unrestricted Hartree-Fock wave function.

In this work we present the particle-breaking Hartree-Fock (PBHF) model which is a mean-field approach to open molecular systems. The interaction of a system with the environment is parametrized through a particle-breaking term in the molecular Hamiltonian. The PBHF wave function is constructed through an exponential unitary transformation of a Slater determinant with a given number of electrons. We consider only the closed-shell formalism. The parametrization results in a linear combination of Slater determinants with different numbers of electrons, i.e., the PBHF wave function is not an eigenfunction of the number operator. As a result, the density matrix may have fractional occupations which are, because of the unitary parametrization, always between 0.0 and 2.0. The occupations are optimized simultaneously with the orbitals, using the trust-region optimization procedure. In the limit of a particle-conserving Hamiltonian, the PBHF optimization will converge to a standard Hartree-Fock wave function. We show that the average number of electrons may be decreased or increased depending on whether the particle-breaking term affects occupied or virtual orbitals.

We present a trust-region optimization of the Edmiston-Ruedenberg orbital localization function. The approach is used to localize both the occupied and the virtual orbitals and is the first demonstration of general virtual orbital localization using the Edmiston-Ruedenberg localization function. In the Edmiston-Ruedenberg approach, the sum of the orbital self-repulsion energies is maximized to obtain the localized orbitals. The Cholesky decomposition reduces the cost of transforming the electron repulsion integrals, and the overall scaling of our implementation is O ( N 4 ) . The optimization is performed with all quantities in the molecular orbital basis, and the localization of the occupied orbitals is often less expensive than the corresponding self-consistent field (SCF) optimization. Furthermore, the occupied orbital localization scales linearly with the basis set. For the virtual space, the cost is significantly higher than the SCF optimization. The orbital spreads of the resulting virtual Edmiston-Ruedenberg orbitals are larger than for other, less expensive, orbital localization functions. This indicates that other localization procedures are more suitable for applications such as local post-Hartree-Fock calculations.

In this article we use MP2 and CCSD(T) calculations for the A24 and S66 data sets to explore how midbond functions can be used to generate cost effective counterpoise corrected supramolecular interaction energies of noncovalent complexes. We use the A24 data set to show that the primary role of midbond functions is not to approach the complete basis set limit, but rather to ensure a balanced description of the molecules and the interaction region (unrelated to the basis set superposition error). The need for balance is a consequence of using atom centered basis sets. In the complete basis set limit, the error will disappear, but reaching the complete basis set limit is not feasible beyond small systems. For S66 we investigate the need for increasing the number of midbond centers. Results show that adding a second midbond center increases the accuracy, but the effect is secondary to changing the atom centered basis set. Further, by comparing calculations using the 3s3p2d1f1g midbond set with using aug-cc-pVDZ and aug-cc-pVTZ as midbond sets, we see that the requirements for the midbond set to be effective, is not just that it contains diffuse functions, but also that high angular momentum functions are included. By comparing two approaches for placing midbond centers we show that results are not particularly sensitive to placement as long as the placement is reasonable., (© 2021 The Authors. Journal of Computational Chemistry published by Wiley Periodicals LLC.)

A revised synthesis of Martin's phosphino-triols (two derivatives) is reported. Once isolated, these thermally sensitive triols were shown to disassemble selectively via an unexpected P-C bond cleavage reaction. This degradation pathway was effectively suppressed via complexation of Al 3+ and Sc 3+ . In the resulting half-cage complexes, the ligand scaffold is bound to each metal (Al 3+ and Sc 3+ , respectively) via all four donor atoms. So far, this κ 4 - P , O , O ', O ″-coordination mode has not been observed for any other phosphino-triol.

The reactivity of a paramagnetic T-shaped cobalt(i) complex, [(iPrboxmi)Co], stabilised by a monoanionic bis(oxazolinylmethylidene)-isoindolate (boxmi) NNN pincer ligand is described. The exposure to carbon monoxide as an additional neutral ligand resulted in the square-planar species [(iPrboxmi)Co(CO)], accompanied by a change in the electronic spin state from S = 1 to S = 0. In contrast, upon treatment with trimethylphosphine the formation of the distorted tetrahedral complex [(iPrboxmi)Co(PMe3)] was observed (S = 1). Reacting [(iPrboxmi)Co] with iodine (I2), organic peroxides (tBu2O2, (SiMe3)2O2) and diphenyldisulphide (Ph2S2) yielded the tetracoordinated complexes [(iPrboxmi)CoI], [(iPrboxmi)Co(OtBu)], [(iPrboxmi)Co(OSiMe3)] and [(iPrboxmi)Co(SPh)], respectively, demonstrating the capability of the boxmi-supported cobalt(i) complex to homolytically cleave bonds and thus its distinct one-electron reactivity. Furthermore, a square-planar cobalt(ii) alkynyl complex [(iPrboxmi)Co(CCArF)] was identified as the main product in the reaction between [(iPrboxmi)Co] and a terminal alkyne, 4-fluoro-1-ethynylbenzene. Putting such species in the context of the previously investigated hydroboration catalysis, its stoichiometric reaction with pinacolborane revealed its potential conversion into a cobalt(ii) hydride complex, thus confirming its original attribution as off-cycle species.

We describe the development of a proximity-induced bio-orthogonal inverse electron demand Diels-Alder reaction that exploits the high-affinity interaction between a dienophile-modified RhoBAST aptamer and its tetramethyl rhodamine methyltetrazine substrate. We applied this concept for covalent RNA labeling in proof-of-principle experiments.

Cobalt(II) alkyl complexes supported by a monoanionic NNN pincer ligand are pre-catalysts for the regioselective hydroboration of terminal alkynes, yielding the Markovnikov products with α:β-(E) ratios of up to 97:3. A cobalt(II) hydride and a cobalt(II) vinyl complex appear to determine the main reaction pathway. In a background reaction the highly reactive hydrido species specifically converts to a coordinatively unsaturated cobalt(I) complex which was found to re-enter the main catalytic cycle., (© 2020 The Authors. Published by Wiley-VCH GmbH.)

New Bulgarian preparations from mioton series (A, B and C) have of late attracted the attention of clinicians. Of a special interest for physiotherapists is mioton B. Broad-scale clinical and experimental trials (41 patients and 75 animals) demonstrated high clinical efficacy of the cream mioton B (Extr. caps. spis. 1.01% 01. bergamotae u ol. lavandulae) induced by ultraphonophoresis. No side effects were registered.