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The first observation of soft X-ray induced excited spin state trapping has been made for [Fe(phen)2(NCS)2] and [Fe(phen)2(NCSe)2] (phen 4;= 4;1,10-phenanthroline) at ca. 45 K, analogous to light induced excited spin state trapping but at much higher energy. Soft X-ray photochemistry has also been observed in the high- and low-spin states of [Fe(phen)2(NCS)2] and [Fe(phen)2(NCSe)2], resulting in the formation of a thermally irreversible low-spin state. The rate of formation of this low-spin state is greater from low than from high spin, and is also greater in [Fe(phen)2(NCSe)2] than in [Fe(phen)2(NCS)2].

A detailed study of the soft X-ray photochemistry occurring in some nickel dithiocarbamate and xanthate complexes has shown that soft X-ray induced photoreduction of [NiIV(S2CNEt2)3][BF4] results in a NiII square-planar species and the rate is dependent on photon flux, photon energy and ligand set, but is essentially independent of temperature. Also, it has been demonstrated that [PPh4][NiII(S2COEt)3] is photoisomerised to a NiII square-planar species on exposure to soft X-rays. The implication for experiments on third generation synchrotron sources is discussed briefly.

A combination of vanadium K- and L-edge XAFS has been used to characterise a series of monomeric oxovanadium(IV), monomeric dioxovanadium(V) and dimeric oxovanadium(V) complexes with oxyoxime and oxyoximate ligands. The K- and L-edge spectra confirm the presence of VV in the dimeric species and the L-edge spectra have been used to discriminate between six-co-ordinate V–N–O–V bridged oxovanadium(V) dimers and seven-co-ordinate phenolate bridged oxovanadium(V) dimers containing η2-N–O groups.