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- W2976016822 abstract "One of the well-established methods of modern quantum crystallography is undoubtedly the X-ray constrained wavefunction (XCW) approach, a technique that enables the determination of wavefunctions which not only minimize the energy of the system under examination, but also reproduce experimental X-ray diffraction data within the limit of the experimental errors. Initially proposed in the framework of the Hartree–Fock method, the strategy has been gradually extended to other techniques of quantum chemistry, but always remaining limited to a single-determinant ansatz for the wavefunction to extract. This limitation has been recently overcome through the development of the novel X-ray constrained spin-coupled (XCSC) approach [Genoni et al. (2018). Chem. Eur. J. 24 , 15507–15511] which merges the XCW philosophy with the traditional spin-coupled strategy of valence bond theory. The main advantage of this new technique is the possibility of extracting traditional chemical descriptors ( e.g. resonance structure weights) compatible with the experimental diffraction measurements, without the need to introduce information a priori or perform analyses a posteriori . This paper provides a detailed theoretical derivation of the fundamental equations at the basis of the XCSC method and also introduces a further advancement of its original version, mainly consisting in the use of molecular orbitals resulting from XCW calculations at the Hartree–Fock level to describe the inactive electrons in the XCSC computations. Furthermore, extensive test calculations, which have been performed by exploiting high-resolution X-ray diffraction data for salicylic acid and by adopting different basis sets, are presented and discussed. The computational tests have shown that the new technique does not suffer from particular convergence problems. Moreover, all the XCSC calculations provided resonance structure weights, spin-coupled orbitals and global electron densities slightly different from those resulting from the corresponding unconstrained computations. These discrepancies can be ascribed to the capability of the novel strategy to capture the information intrinsically contained in the experimental data used as external constraints." @default.
- W2976016822 created "2019-10-03" @default.
- W2976016822 creator A5009850464 @default.
- W2976016822 creator A5036119882 @default.
- W2976016822 creator A5056170111 @default.
- W2976016822 creator A5056978520 @default.
- W2976016822 creator A5078378656 @default.
- W2976016822 date "2019-09-24" @default.
- W2976016822 modified "2023-10-10" @default.
- W2976016822 title "X-ray constrained spin-coupled technique: theoretical details and further assessment of the method" @default.
- W2976016822 cites W1939179553 @default.
- W2976016822 cites W1966587798 @default.
- W2976016822 cites W1968699101 @default.
- W2976016822 cites W1983966907 @default.
- W2976016822 cites W1986978270 @default.
- W2976016822 cites W1987475864 @default.
- W2976016822 cites W1989336284 @default.
- W2976016822 cites W1989602826 @default.
- W2976016822 cites W1990608474 @default.
- W2976016822 cites W1992114784 @default.
- W2976016822 cites W1993961310 @default.
- W2976016822 cites W1994822605 @default.
- W2976016822 cites W1997111475 @default.
- W2976016822 cites W1998611317 @default.
- W2976016822 cites W2000599031 @default.
- W2976016822 cites W2001074081 @default.
- W2976016822 cites W2003376663 @default.
- W2976016822 cites W2003917567 @default.
- W2976016822 cites W2004598898 @default.
- W2976016822 cites W2005642208 @default.
- W2976016822 cites W2006595690 @default.
- W2976016822 cites W2007333557 @default.
- W2976016822 cites W2008345487 @default.
- W2976016822 cites W2008646838 @default.
- W2976016822 cites W2010026471 @default.
- W2976016822 cites W2011079470 @default.
- W2976016822 cites W2011795420 @default.
- W2976016822 cites W2013807722 @default.
- W2976016822 cites W2014209007 @default.
- W2976016822 cites W2015115007 @default.
- W2976016822 cites W2015817826 @default.
- W2976016822 cites W2015856977 @default.
- W2976016822 cites W2016555809 @default.
- W2976016822 cites W2018541907 @default.
- W2976016822 cites W2019398514 @default.
- W2976016822 cites W2036716364 @default.
- W2976016822 cites W2037308395 @default.
- W2976016822 cites W2037471369 @default.
- W2976016822 cites W2039056309 @default.
- W2976016822 cites W2039492122 @default.
- W2976016822 cites W2040134477 @default.
- W2976016822 cites W2042495131 @default.
- W2976016822 cites W2043821644 @default.
- W2976016822 cites W2046604198 @default.
- W2976016822 cites W2048939476 @default.
- W2976016822 cites W2051917050 @default.
- W2976016822 cites W2053696949 @default.
- W2976016822 cites W2053940560 @default.
- W2976016822 cites W2056636696 @default.
- W2976016822 cites W2059052476 @default.
- W2976016822 cites W2061678210 @default.
- W2976016822 cites W2063433565 @default.
- W2976016822 cites W2070036988 @default.
- W2976016822 cites W2070141598 @default.
- W2976016822 cites W2070154208 @default.
- W2976016822 cites W2071312497 @default.
- W2976016822 cites W2071922898 @default.
- W2976016822 cites W2072215160 @default.
- W2976016822 cites W2080385432 @default.
- W2976016822 cites W2080683259 @default.
- W2976016822 cites W2082806933 @default.
- W2976016822 cites W2083298752 @default.
- W2976016822 cites W2083522962 @default.
- W2976016822 cites W2085354509 @default.
- W2976016822 cites W2086279269 @default.
- W2976016822 cites W2088929871 @default.
- W2976016822 cites W2089653166 @default.
- W2976016822 cites W2090765455 @default.
- W2976016822 cites W2093914988 @default.
- W2976016822 cites W2100104156 @default.
- W2976016822 cites W2102164624 @default.
- W2976016822 cites W2114911307 @default.
- W2976016822 cites W2122112911 @default.
- W2976016822 cites W2125122393 @default.
- W2976016822 cites W2133944077 @default.
- W2976016822 cites W2138174729 @default.
- W2976016822 cites W2142775980 @default.
- W2976016822 cites W2143734934 @default.
- W2976016822 cites W2145645964 @default.
- W2976016822 cites W2149161375 @default.
- W2976016822 cites W2149551621 @default.
- W2976016822 cites W2161298053 @default.
- W2976016822 cites W2289296442 @default.
- W2976016822 cites W2313047910 @default.
- W2976016822 cites W2313169640 @default.
- W2976016822 cites W2317168681 @default.
- W2976016822 cites W2333147588 @default.
- W2976016822 cites W2481592298 @default.