( ( ( An impulse ) ( of ( k ( times ( the ( long ( range force ) ) ) ) ) ) ) ( ( is ( applied ( to ( ( ( the system ) ( ( every k ) timesteps ) ) ( -LRB- ( ( i.e. ( , ( ( the ( r-RESPA integrator ) ) ( is used ) ) ) ) -RRB- ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT An) (NN impulse)) (PP (IN of) (NP (NP (NN k)) (PP (CC times) (NP (DT the) (JJ long) (NN range) (NN force)))))) (VP (VBZ is) (VP (VBN applied) (PP (TO to) (NP (NP (DT the) (NN system)) (SBAR (S (NP (DT every) (NN k)) (VP (VBZ timesteps)))) (PRN (-LRB- -LRB-) (S (NP (NNP i.e.)) (, ,) (NP (DT the) (JJ r-RESPA) (NN integrator)) (VP (VBZ is) (VP (VBN used)))) (-RRB- -RRB-)))))) (. .)))
An impulse of k times the long range force is applied to the system every k timesteps (i.e., the r-RESPA integrator is used).
(ROOT (S (NP (NNP Impulse)) (VP (VBZ is) (NP (NP (DT the) (NN quantity)) (PP (IN of) (NP (NP (NN force)) (VP (VBN multiplied) (PP (IN by) (NP (NP (DT the) (NN time)) (SBAR (S (NP (PRP it)) (VP (VBZ is) (VP (VBN applied)))))))))))) (. .)))